Crystalline lens paradoxes revisited: significance of age-related restructuring of the GRIN.

Science.gov (United States)

Sheil, Conor J; Goncharov, Alexander V

2017-09-01

The accommodating volume-constant age-dependent optical (AVOCADO) model of the crystalline lens is used to explore the age-related changes in ocular power and spherical aberration. The additional parameter m in the GRIN lens model allows decoupling of the axial and radial GRIN profiles, and is used to stabilise the age-related change in ocular power. Data for age-related changes in ocular geometry and lens parameter P in the axial GRIN profile were taken from published experimental data. In our age-dependent eye model, the ocular refractive power shows behaviour similar to the previously unexplained "lens paradox". Furthermore, ocular spherical aberration agrees with the data average, in contrast to the proposed "spherical aberration paradox". The additional flexibility afforded by parameter m , which controls the ratio of the axial and radial GRIN profile exponents, has allowed us to study the restructuring of the lens GRIN medium with age, resulting in a new interpretation of the origin of the power and spherical aberration paradoxes. Our findings also contradict the conceptual idea that the ageing eye is similar to the accommodating eye.

The thresholds for statistical and clinical significance

DEFF Research Database (Denmark)

Jakobsen, Janus Christian; Gluud, Christian; Winkel, Per

2014-01-01

BACKGROUND: Thresholds for statistical significance are insufficiently demonstrated by 95% confidence intervals or P-values when assessing results from randomised clinical trials. First, a P-value only shows the probability of getting a result assuming that the null hypothesis is true and does...... not reflect the probability of getting a result assuming an alternative hypothesis to the null hypothesis is true. Second, a confidence interval or a P-value showing significance may be caused by multiplicity. Third, statistical significance does not necessarily result in clinical significance. Therefore...... of the probability that a given trial result is compatible with a 'null' effect (corresponding to the P-value) divided by the probability that the trial result is compatible with the intervention effect hypothesised in the sample size calculation; (3) adjust the confidence intervals and the statistical significance...

Age and gender-related differences in mitral cells of olfactory bulb

International Nuclear Information System (INIS)

Haq, I.H.; Tahir, M.

2008-01-01

To investigate the age and gender-related differences in mitral cells of the human cadaveric olfactory bulbs. Sixty olfactory bulbs, 30 each from male and female (age 20-76 years) human cadavers divided into six groups of age and gender-wise were collected from the mortuary of the King Edward Medical University, Lahore. Mitral cells were counted and their diameter was calculated from 10 micro m thick cresyl violet stained histological sections. Statistical analysis was done using ANOVA for age-related differences and independent t-test for gender-related differences. There was significant reduction in the number of mitral cells and diameter of their nuclei with age. There was significant decrease in the number of mitral cells in males, between groups I and II (p < 0.001); II and III (p < 0.001); and I and III (p < 0.001); statistically significant decrease also occurred in females, between groups IV and V (p < 0.001); V and VI (p < 0.001); and IV and VI (p < 0.001). In most cases, the distance between individual mitral cells was seen to be much greater than in younger group. In group VI, few mitral cells were observed in the cell layer. There was also significant decrease in the diameter of mitral cell nuclei in males, between groups I and III (p < 0.001); and II and III (p < 0.010); in females, between groups IV and VI (p < 0.001); and V and VI (p < 0.001). No gender-related differences were observed. The number of mitral cells and diameter of their nuclei decreased with advancing age. (author)

Serious fighting-related injuries produce a significant reduction in intelligence.

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Schwartz, Joseph A; Beaver, Kevin M

2013-10-01

Fighting-related injuries are common among adolescents within the United States, but how such injuries relate to subsequent cognitive functioning remains unclear. In particular, the long-term effect of fighting-related injuries suffered during important developmental periods, such as adolescence, on subsequent cognitive functioning has been overlooked by previous studies. The purpose of this study is to examine the association between sustaining serious fighting-related injuries and changes in verbal intelligence (IQ) over a 5- to 6-year time period. Longitudinal multivariate statistical models were used to analyze data from the National Longitudinal Study of Adolescent Health collected between 1994 and 2002 and analyzed in 2013. Even a single fighting-related injury resulted in a significant reduction in IQ over time even after controlling for age, race, sex, and changes in socioeconomic status (SES) over the study period. Additionally, females experienced a significantly greater reduction in IQ from each fighting-related injury than males. Fighting-related injuries have a significant impact on subsequent cognitive functioning and intelligence. The implications for future policies and research are discussed in more detail. Copyright © 2013 Society for Adolescent Health and Medicine. Published by Elsevier Inc. All rights reserved.

Age-related changes in factor VII proteolysis in vivo.

Science.gov (United States)

Ofosu, F A; Craven, S; Dewar, L; Anvari, N; Andrew, M; Blajchman, M A

1996-08-01

Previous studies have reported that pre-operative plasmas of patients over the age of 40 years who developed post-operative deep vein thrombosis (DVT) had approximately twice the amount of proteolysed factor VII found in plasmas of patients in whom prophylaxis with heparin or low M(r) heparin was successful. These and other studies also reported higher concentrations of thrombin-antithrombin III in pre- and post-operative plasmas of patients who developed post-operative thrombosis than in plasmas of patients in whom prophylaxis was successful. Whether the extent of factor VII proteolysis seen in the patients who developed post-operative DVT is related to the severity of their disease or age is not known. This report investigated age-related changes in the concentrations of total factor VII protein, factor VII zymogen, factor VIIa, tissue factor pathway inhibitor, thrombin-antithrombin III, and prothrombin fragment 1 + 2 in normal plasmas and the relationships between these parameters. With the exception of thrombin-antithrombin III, statistically significant increases in the concentrations of these parameters with age were found. Additionally, the differences between the concentrations of total factor VII protein and factor VII zymogen, an index factor VII proteolysis in vivo, were statistically significant only for individuals over age 40. Using linear regression analysis, a significant correlation was found to exist between the concentrations of plasma factor VIIa and prothrombin fragment 1 + 2. Since factor VIIa-tissue factor probably initiates coagulation in vivo, we hypothesize that the elevated plasma factor VIIa (reflecting a less tightly regulated tissue factor activity and therefore increased thrombin production in vivo) accounts for the high risk for post-operative thrombosis seen in individuals over the age of 40.

The insignificance of statistical significance testing

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Johnson, Douglas H.

1999-01-01

Despite their use in scientific journals such as The Journal of Wildlife Management, statistical hypothesis tests add very little value to the products of research. Indeed, they frequently confuse the interpretation of data. This paper describes how statistical hypothesis tests are often viewed, and then contrasts that interpretation with the correct one. I discuss the arbitrariness of P-values, conclusions that the null hypothesis is true, power analysis, and distinctions between statistical and biological significance. Statistical hypothesis testing, in which the null hypothesis about the properties of a population is almost always known a priori to be false, is contrasted with scientific hypothesis testing, which examines a credible null hypothesis about phenomena in nature. More meaningful alternatives are briefly outlined, including estimation and confidence intervals for determining the importance of factors, decision theory for guiding actions in the face of uncertainty, and Bayesian approaches to hypothesis testing and other statistical practices.

Significance levels for studies with correlated test statistics.

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Shi, Jianxin; Levinson, Douglas F; Whittemore, Alice S

2008-07-01

When testing large numbers of null hypotheses, one needs to assess the evidence against the global null hypothesis that none of the hypotheses is false. Such evidence typically is based on the test statistic of the largest magnitude, whose statistical significance is evaluated by permuting the sample units to simulate its null distribution. Efron (2007) has noted that correlation among the test statistics can induce substantial interstudy variation in the shapes of their histograms, which may cause misleading tail counts. Here, we show that permutation-based estimates of the overall significance level also can be misleading when the test statistics are correlated. We propose that such estimates be conditioned on a simple measure of the spread of the observed histogram, and we provide a method for obtaining conditional significance levels. We justify this conditioning using the conditionality principle described by Cox and Hinkley (1974). Application of the method to gene expression data illustrates the circumstances when conditional significance levels are needed.

Gender and Age Related Effects While Watching TV Advertisements: An EEG Study.

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Cartocci, Giulia; Cherubino, Patrizia; Rossi, Dario; Modica, Enrica; Maglione, Anton Giulio; di Flumeri, Gianluca; Babiloni, Fabio

2016-01-01

The aim of the present paper is to show how the variation of the EEG frontal cortical asymmetry is related to the general appreciation perceived during the observation of TV advertisements, in particular considering the influence of the gender and age on it. In particular, we investigated the influence of the gender on the perception of a car advertisement (Experiment 1) and the influence of the factor age on a chewing gum commercial (Experiment 2). Experiment 1 results showed statistically significant higher approach values for the men group throughout the commercial. Results from Experiment 2 showed significant lower values by older adults for the spot, containing scenes not very enjoyed by them. In both studies, there was no statistical significant difference in the scene relative to the product offering between the experimental populations, suggesting the absence in our study of a bias towards the specific product in the evaluated populations. These evidences state the importance of the creativity in advertising, in order to attract the target population.

Variations with time and age in the relative risks of solid cancer incidence after radiation exposure

International Nuclear Information System (INIS)

Little, M.P.; Muirhead, C.R.; de Vathaire, F.; Charles, M.W.

1997-01-01

The Japanese atomic bomb survivor cancer incidence dataset and data on five groups exposed to radiation for medical reasons in childhood are analysed and evidence found for a reduction in the radiation-induced relative risk of cancers other than leukaemia with increasing time since exposure and age at exposure. The rate of the reductions in relative risk with time since exposure are not significantly different for those exposed in childhood and for those exposed in adulthood, if adjustment is made for the effects on the relative risk of age at exposure. For those irradiated in childhood, there is a statistically significant annual reduction of 5.8% (95% Cl 2.8, 8.9) in excess relative risk, and there are no strong indications of inter-cohort heterogeniety in the speed of reduction of relative risk. After adjustment for the effects of age at exposure, there is a significant annual reduction of 3.6% (95% Cl 1.6, 5.6) in excess relative risk in all age-at-exposure groups. There are significant reductions of 5.2% (95% Cl 3.7, 6.8) in excess relative risk per year of age at exposure. There are statistically significant (P = 0.04) interactions between the exponential adjustments to the excess relative risk for age at exposure and time since exposure in the Japanese data, but no indications (P = 0.38) of such interactions when powers of time since exposure and attained age are used to adjust the excess relative risk, so that the fit of the model with power adjustments is to be preferred to that of the model with exponential adjustments. (author)

Audiometric changes with age in Hiroshima: a statistical study

Energy Technology Data Exchange (ETDEWEB)

Hollingsworth, J W; Ishii, Goro

1960-10-01

Audiometry observations were analyzed for 290 irradiated survivors of the 1945 atomic bomb in Hiroshima and in 293 nonirradiated subjects. The study was undertaken in order to determine the age changes in audiology in irradiated and nonirradiated subjects as well as to investigate the pattern of hearing levels in a Japanese population for comparison with patterns in Caucasians. The following statistical observations were made. Correlation between hearing levels for right and left ear. Correlation between hearing levels at various cycles. Changes in hearing levels by age and sex. The relation between age and decibel loss was not linear and correlation ratios with age were 0.45 to 0.72. Audiometry seems to be of some value as one of a battery of tests of physiologic aging designed for detection of irradiation induced nonspecific aging acceleration. In this relatively small sample, no differences in hearing acuity were detected in the atomic bomb survivors as compared with the control sample. 6 references, 3 figures, 9 tables.

Age and sex differences in game-related statistics which discriminate winners from losers in elite basketball games

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Haruhiko Madarame

2018-02-01

Full Text Available Abstract AIMS To advance knowledge of long-term development of basketball players, this study investigated age and sex differences in game-related statistics which discriminate winners from losers in World Basketball Championships held after the 2010 rule change. METHODS A total of 935 games from six categories (under-17, under-19 and open age for both men and women were analyzed. All games were classified into three types (balanced, unbalanced and very unbalanced according to point differential by a k-means cluster analysis. A discriminant analysis was performed to identify game-related statistics which discriminate winners from losers in each game type. An absolute value of a structural coefficient (SC equal to or above 0.30 was considered relevant for the discrimination. RESULTS In balanced games, assists discriminated winners from losers in open games (men, |SC| = 0.32; women, |SC| = 0.34, whereas successful free throws did so in under-17 games (men, |SC| = 0.30; women, |SC| = 0.31. Successful 2-point field goals discriminated winners from losers only in women’s games (under-19, |SC| = 0.38; open, |SC| = 0.36. CONCLUSION There were three novel findings in balanced games: 1 successful free throws but not assists discriminated winners from losers in under-17 games; 2 successful 2-point field goals discriminated winners from losers in women’s games but not in men’s games; and 3 discriminating power of successful 3-point field goals was extremely small in women’s games. These results may be related to the new rules for the shot clock and the 3-point distance.

Electrocardiographic findings related to aging

Energy Technology Data Exchange (ETDEWEB)

Ueda, Shoichi; Yano, Katsuhiko

1962-12-12

More than 3000 electrocardiographic tracings for the ABCC-JNIH Adult Health Study Sample were studied to detect any specific abnormalities or nonspecific age changes in relation to possible radiation effects upon the cardiovascular system. The 4 comparison groups were studied with respect to the prevalence of electrocardiographic abnormalities and an electrocardiographic aging index which was defined to evaluate physiological change with age. Statistically significant differences were observed in the following aspects: In males aged 50 to 59, the prevalence of major electrocardiographic abnormalities was highest in the group located nearest the hypocenter. This was not observed in other age groups. In females, the prevalence of QRS high voltage was highest in Group 2 but low in Group 1. This trend was consistent in all age groups. These findings were not fully accounted for by differences in blood pressure, heart size, body weight or serum cholesterol values. In the age trend curve of the electrocardiographic aging index, a difference was observed among comparison groups in both sexes. This difference in electrocardiographic aging index is mainly attributed to T/sub I/ amplitude for males and R/sub II/ amplitude and QRS axis for females. Interpretation of these findings is rather difficult since very little has been known about radiation effects upon the cardiovascular system in humans. Further intensive studies are desired on the basis of the clues suggested in this report. 16 references, 3 figures, 31 tables.

Age-related contrast enhancement study of normal bone marrow in lumbar spinal MR imaging

International Nuclear Information System (INIS)

Kim, Young A; Ha, Doo Hoe

1999-01-01

The purpose of this study was to evaluate the degree of contrast enhancement of normal bone marrow in L-spine relating to aging and to determine the range of contrast enhancement in normal bone marrow. We analyzed a total of 120 patients (20 per decade) who had undergone lumbar spinal MRI and who ranged in age from the 2nd decade to more than the 7th. Bone marrow revealed no abnormal pathology. Sagittal T1-weighted spin echo sequences were obtained before and after gadolinium administration. For each sequence, a region of interest was drawn within the L1 vertebral body from the midsagittal slice. Signal intensity (SI) values of each sequence were ascertained and the percentage increase in SI was calculated. After contrast enhancement, lumbar MRI revealed no statistically significant in the percentage increase in SI of normal bone marrow in relation to aging. Most patients (99%) however showed an SI increase of between 10% and 49%. In only four, none of whom were aged over 40, was this increase above 50%. Lumbar MRI, revealed no statistically significant difference in percentage increase in SI in normal bone marrow relating to aging, but when the increase is above 50% in a patient aged over 40, bone marrow pathology should be further investigated

Gender and Age Related Effects While Watching TV Advertisements: An EEG Study

Directory of Open Access Journals (Sweden)

Giulia Cartocci

2016-01-01

Full Text Available The aim of the present paper is to show how the variation of the EEG frontal cortical asymmetry is related to the general appreciation perceived during the observation of TV advertisements, in particular considering the influence of the gender and age on it. In particular, we investigated the influence of the gender on the perception of a car advertisement (Experiment 1 and the influence of the factor age on a chewing gum commercial (Experiment 2. Experiment 1 results showed statistically significant higher approach values for the men group throughout the commercial. Results from Experiment 2 showed significant lower values by older adults for the spot, containing scenes not very enjoyed by them. In both studies, there was no statistical significant difference in the scene relative to the product offering between the experimental populations, suggesting the absence in our study of a bias towards the specific product in the evaluated populations. These evidences state the importance of the creativity in advertising, in order to attract the target population.

Common pitfalls in statistical analysis: "P" values, statistical significance and confidence intervals

Directory of Open Access Journals (Sweden)

Priya Ranganathan

2015-01-01

Full Text Available In the second part of a series on pitfalls in statistical analysis, we look at various ways in which a statistically significant study result can be expressed. We debunk some of the myths regarding the ′P′ value, explain the importance of ′confidence intervals′ and clarify the importance of including both values in a paper

Intravitreal bevacizumab (Avastin) for neovascular age-related macular degeneration in treatment-naive patients

DEFF Research Database (Denmark)

Pedersen, Karen Bjerg; Sjølie, Anne Katrin; Møller, Flemming

2008-01-01

Abstract. Purpose: To report the effects of intravitreal bevacizumab (Avastin((R))) in treatment-naive patients with exudative age-related macular degeneration (ARMD) assessed by visual acuity (VA), optical coherence tomography (OCT) and contrast sensitivity. Methods: A prospective, uncontrolled...... was not statistically significant. Mean macular thickness decreased significantly from baseline to all follow-up examinations (P Macular thickness improved significantly at all time...

Statistical vs. Economic Significance in Economics and Econometrics: Further comments on McCloskey & Ziliak

DEFF Research Database (Denmark)

Engsted, Tom

I comment on the controversy between McCloskey & Ziliak and Hoover & Siegler on statistical versus economic significance, in the March 2008 issue of the Journal of Economic Methodology. I argue that while McCloskey & Ziliak are right in emphasizing 'real error', i.e. non-sampling error that cannot...... be eliminated through specification testing, they fail to acknowledge those areas in economics, e.g. rational expectations macroeconomics and asset pricing, where researchers clearly distinguish between statistical and economic significance and where statistical testing plays a relatively minor role in model...

Strategies for Testing Statistical and Practical Significance in Detecting DIF with Logistic Regression Models

Science.gov (United States)

Fidalgo, Angel M.; Alavi, Seyed Mohammad; Amirian, Seyed Mohammad Reza

2014-01-01

This study examines three controversial aspects in differential item functioning (DIF) detection by logistic regression (LR) models: first, the relative effectiveness of different analytical strategies for detecting DIF; second, the suitability of the Wald statistic for determining the statistical significance of the parameters of interest; and…

Statistical ecology comes of age

Science.gov (United States)

Gimenez, Olivier; Buckland, Stephen T.; Morgan, Byron J. T.; Bez, Nicolas; Bertrand, Sophie; Choquet, Rémi; Dray, Stéphane; Etienne, Marie-Pierre; Fewster, Rachel; Gosselin, Frédéric; Mérigot, Bastien; Monestiez, Pascal; Morales, Juan M.; Mortier, Frédéric; Munoz, François; Ovaskainen, Otso; Pavoine, Sandrine; Pradel, Roger; Schurr, Frank M.; Thomas, Len; Thuiller, Wilfried; Trenkel, Verena; de Valpine, Perry; Rexstad, Eric

2014-01-01

The desire to predict the consequences of global environmental change has been the driver towards more realistic models embracing the variability and uncertainties inherent in ecology. Statistical ecology has gelled over the past decade as a discipline that moves away from describing patterns towards modelling the ecological processes that generate these patterns. Following the fourth International Statistical Ecology Conference (1–4 July 2014) in Montpellier, France, we analyse current trends in statistical ecology. Important advances in the analysis of individual movement, and in the modelling of population dynamics and species distributions, are made possible by the increasing use of hierarchical and hidden process models. Exciting research perspectives include the development of methods to interpret citizen science data and of efficient, flexible computational algorithms for model fitting. Statistical ecology has come of age: it now provides a general and mathematically rigorous framework linking ecological theory and empirical data. PMID:25540151

Statistical ecology comes of age.

Science.gov (United States)

Gimenez, Olivier; Buckland, Stephen T; Morgan, Byron J T; Bez, Nicolas; Bertrand, Sophie; Choquet, Rémi; Dray, Stéphane; Etienne, Marie-Pierre; Fewster, Rachel; Gosselin, Frédéric; Mérigot, Bastien; Monestiez, Pascal; Morales, Juan M; Mortier, Frédéric; Munoz, François; Ovaskainen, Otso; Pavoine, Sandrine; Pradel, Roger; Schurr, Frank M; Thomas, Len; Thuiller, Wilfried; Trenkel, Verena; de Valpine, Perry; Rexstad, Eric

2014-12-01

The desire to predict the consequences of global environmental change has been the driver towards more realistic models embracing the variability and uncertainties inherent in ecology. Statistical ecology has gelled over the past decade as a discipline that moves away from describing patterns towards modelling the ecological processes that generate these patterns. Following the fourth International Statistical Ecology Conference (1-4 July 2014) in Montpellier, France, we analyse current trends in statistical ecology. Important advances in the analysis of individual movement, and in the modelling of population dynamics and species distributions, are made possible by the increasing use of hierarchical and hidden process models. Exciting research perspectives include the development of methods to interpret citizen science data and of efficient, flexible computational algorithms for model fitting. Statistical ecology has come of age: it now provides a general and mathematically rigorous framework linking ecological theory and empirical data.

Health significance and statistical uncertainty. The value of P-value.

Science.gov (United States)

Consonni, Dario; Bertazzi, Pier Alberto

2017-10-27

The P-value is widely used as a summary statistics of scientific results. Unfortunately, there is a widespread tendency to dichotomize its value in "P0.05" ("statistically not significant"), with the former implying a "positive" result and the latter a "negative" one. To show the unsuitability of such an approach when evaluating the effects of environmental and occupational risk factors. We provide examples of distorted use of P-value and of the negative consequences for science and public health of such a black-and-white vision. The rigid interpretation of P-value as a dichotomy favors the confusion between health relevance and statistical significance, discourages thoughtful thinking, and distorts attention from what really matters, the health significance. A much better way to express and communicate scientific results involves reporting effect estimates (e.g., risks, risks ratios or risk differences) and their confidence intervals (CI), which summarize and convey both health significance and statistical uncertainty. Unfortunately, many researchers do not usually consider the whole interval of CI but only examine if it includes the null-value, therefore degrading this procedure to the same P-value dichotomy (statistical significance or not). In reporting statistical results of scientific research present effects estimates with their confidence intervals and do not qualify the P-value as "significant" or "not significant".

Relative Age Effect: Relationship between Anthropometric and Fitness Skills in Youth Soccer

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Aristotelis GIOLDASIS

2015-12-01

Full Text Available The aim of the study was to determine the relationship between anthropometric and fitness skills in youth soccer players according to their related age. The existence of relative age effect was also examined. Anthropometric as well fitness variables such as height, weight, BMI, body mass, flexibility, balance, reaction time, jumping ability, and endurance of the lower limb were assessed in 347 amateur young players. Participants’ age ranged from 9 to 16 (M= 12.43, SD= 2.17. Analyses of variance indicated many significant differences among players of different birth quartile (from P< .001 to P< .05 for all the skills that were examined. The chi square test that was conducted to assess the distribution of players, showed that for all four different age groups no statistically significant difference was found regarding the birth quartile of players. In countries that training groups include 2 different age categories, anthropometric and fitness differences because of relative age effect are heightened. However, physical and physiological variables are inaccurate in predicting later success of players. Thus talent identification systems should provide equal opportunities for talented but related younger players. It is suggested an on-going talent identification using a multidimensional evaluation form including technical, physiological, physical, tactical, and psychological parameters.

Aging Affects Adaptation to Sound-Level Statistics in Human Auditory Cortex.

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Herrmann, Björn; Maess, Burkhard; Johnsrude, Ingrid S

2018-02-21

Optimal perception requires efficient and adaptive neural processing of sensory input. Neurons in nonhuman mammals adapt to the statistical properties of acoustic feature distributions such that they become sensitive to sounds that are most likely to occur in the environment. However, whether human auditory responses adapt to stimulus statistical distributions and how aging affects adaptation to stimulus statistics is unknown. We used MEG to study how exposure to different distributions of sound levels affects adaptation in auditory cortex of younger (mean: 25 years; n = 19) and older (mean: 64 years; n = 20) adults (male and female). Participants passively listened to two sound-level distributions with different modes (either 15 or 45 dB sensation level). In a control block with long interstimulus intervals, allowing neural populations to recover from adaptation, neural response magnitudes were similar between younger and older adults. Critically, both age groups demonstrated adaptation to sound-level stimulus statistics, but adaptation was altered for older compared with younger people: in the older group, neural responses continued to be sensitive to sound level under conditions in which responses were fully adapted in the younger group. The lack of full adaptation to the statistics of the sensory environment may be a physiological mechanism underlying the known difficulty that older adults have with filtering out irrelevant sensory information. SIGNIFICANCE STATEMENT Behavior requires efficient processing of acoustic stimulation. Animal work suggests that neurons accomplish efficient processing by adjusting their response sensitivity depending on statistical properties of the acoustic environment. Little is known about the extent to which this adaptation to stimulus statistics generalizes to humans, particularly to older humans. We used MEG to investigate how aging influences adaptation to sound-level statistics. Listeners were presented with sounds drawn from

Common pitfalls in statistical analysis: “P” values, statistical significance and confidence intervals

Science.gov (United States)

Ranganathan, Priya; Pramesh, C. S.; Buyse, Marc

2015-01-01

In the second part of a series on pitfalls in statistical analysis, we look at various ways in which a statistically significant study result can be expressed. We debunk some of the myths regarding the ‘P’ value, explain the importance of ‘confidence intervals’ and clarify the importance of including both values in a paper PMID:25878958

Testing statistical significance scores of sequence comparison methods with structure similarity

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Leunissen Jack AM

2006-10-01

Full Text Available Abstract Background In the past years the Smith-Waterman sequence comparison algorithm has gained popularity due to improved implementations and rapidly increasing computing power. However, the quality and sensitivity of a database search is not only determined by the algorithm but also by the statistical significance testing for an alignment. The e-value is the most commonly used statistical validation method for sequence database searching. The CluSTr database and the Protein World database have been created using an alternative statistical significance test: a Z-score based on Monte-Carlo statistics. Several papers have described the superiority of the Z-score as compared to the e-value, using simulated data. We were interested if this could be validated when applied to existing, evolutionary related protein sequences. Results All experiments are performed on the ASTRAL SCOP database. The Smith-Waterman sequence comparison algorithm with both e-value and Z-score statistics is evaluated, using ROC, CVE and AP measures. The BLAST and FASTA algorithms are used as reference. We find that two out of three Smith-Waterman implementations with e-value are better at predicting structural similarities between proteins than the Smith-Waterman implementation with Z-score. SSEARCH especially has very high scores. Conclusion The compute intensive Z-score does not have a clear advantage over the e-value. The Smith-Waterman implementations give generally better results than their heuristic counterparts. We recommend using the SSEARCH algorithm combined with e-values for pairwise sequence comparisons.

Gene expression markers of age-related inflammation in two human cohorts.

Science.gov (United States)

Pilling, Luke C; Joehanes, Roby; Melzer, David; Harries, Lorna W; Henley, William; Dupuis, Josée; Lin, Honghuang; Mitchell, Marcus; Hernandez, Dena; Ying, Sai-Xia; Lunetta, Kathryn L; Benjamin, Emelia J; Singleton, Andrew; Levy, Daniel; Munson, Peter; Murabito, Joanne M; Ferrucci, Luigi

2015-10-01

Chronically elevated circulating inflammatory markers are common in older persons but mechanisms are unclear. Many blood transcripts (>800 genes) are associated with interleukin-6 protein levels (IL6) independent of age. We aimed to identify gene transcripts statistically mediating, as drivers or responders, the increasing levels of IL6 protein in blood at older ages. Blood derived in-vivo RNA from the Framingham Heart Study (FHS, n=2422, ages 40-92 yrs) and InCHIANTI study (n=694, ages 30-104 yrs), with Affymetrix and Illumina expression arrays respectively (>17,000 genes tested), were tested for statistical mediation of the age-IL6 association using resampling techniques, adjusted for confounders and multiple testing. In FHS, IL6 expression was not associated with IL6 protein levels in blood. 102 genes (0.6% of 17,324 expressed) statistically mediated the age-IL6 association of which 25 replicated in InCHIANTI (including 5 of the 10 largest effect genes). The largest effect gene (SLC4A10, coding for NCBE, a sodium bicarbonate transporter) mediated 19% (adjusted CI 8.9 to 34.1%) and replicated by PCR in InCHIANTI (n=194, 35.6% mediated, p=0.01). Other replicated mediators included PRF1 (perforin, a cytolytic protein in cytotoxic T lymphocytes and NK cells) and IL1B (Interleukin 1 beta): few other cytokines were significant mediators. This transcriptome-wide study on human blood identified a small distinct set of genes that statistically mediate the age-IL6 association. Findings are robust across two cohorts and different expression technologies. Raised IL6 levels may not derive from circulating white cells in age related inflammation. Published by Elsevier Inc.

Calculating statistical distributions from operator relations: The statistical distributions of various intermediate statistics

International Nuclear Information System (INIS)

Dai, Wu-Sheng; Xie, Mi

2013-01-01

In this paper, we give a general discussion on the calculation of the statistical distribution from a given operator relation of creation, annihilation, and number operators. Our result shows that as long as the relation between the number operator and the creation and annihilation operators can be expressed as a † b=Λ(N) or N=Λ −1 (a † b), where N, a † , and b denote the number, creation, and annihilation operators, i.e., N is a function of quadratic product of the creation and annihilation operators, the corresponding statistical distribution is the Gentile distribution, a statistical distribution in which the maximum occupation number is an arbitrary integer. As examples, we discuss the statistical distributions corresponding to various operator relations. In particular, besides the Bose–Einstein and Fermi–Dirac cases, we discuss the statistical distributions for various schemes of intermediate statistics, especially various q-deformation schemes. Our result shows that the statistical distributions corresponding to various q-deformation schemes are various Gentile distributions with different maximum occupation numbers which are determined by the deformation parameter q. This result shows that the results given in much literature on the q-deformation distribution are inaccurate or incomplete. -- Highlights: ► A general discussion on calculating statistical distribution from relations of creation, annihilation, and number operators. ► A systemic study on the statistical distributions corresponding to various q-deformation schemes. ► Arguing that many results of q-deformation distributions in literature are inaccurate or incomplete

Statistical significance of epidemiological data. Seminar: Evaluation of epidemiological studies

International Nuclear Information System (INIS)

Weber, K.H.

1993-01-01

In stochastic damages, the numbers of events, e.g. the persons who are affected by or have died of cancer, and thus the relative frequencies (incidence or mortality) are binomially distributed random variables. Their statistical fluctuations can be characterized by confidence intervals. For epidemiologic questions, especially for the analysis of stochastic damages in the low dose range, the following issues are interesting: - Is a sample (a group of persons) with a definite observed damage frequency part of the whole population? - Is an observed frequency difference between two groups of persons random or statistically significant? - Is an observed increase or decrease of the frequencies with increasing dose random or statistically significant and how large is the regression coefficient (= risk coefficient) in this case? These problems can be solved by sttistical tests. So-called distribution-free tests and tests which are not bound to the supposition of normal distribution are of particular interest, such as: - χ 2 -independence test (test in contingency tables); - Fisher-Yates-test; - trend test according to Cochran; - rank correlation test given by Spearman. These tests are explained in terms of selected epidemiologic data, e.g. of leukaemia clusters, of the cancer mortality of the Japanese A-bomb survivors especially in the low dose range as well as on the sample of the cancer mortality in the high background area in Yangjiang (China). (orig.) [de

Statistical significance versus clinical relevance.

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van Rijn, Marieke H C; Bech, Anneke; Bouyer, Jean; van den Brand, Jan A J G

2017-04-01

In March this year, the American Statistical Association (ASA) posted a statement on the correct use of P-values, in response to a growing concern that the P-value is commonly misused and misinterpreted. We aim to translate these warnings given by the ASA into a language more easily understood by clinicians and researchers without a deep background in statistics. Moreover, we intend to illustrate the limitations of P-values, even when used and interpreted correctly, and bring more attention to the clinical relevance of study findings using two recently reported studies as examples. We argue that P-values are often misinterpreted. A common mistake is saying that P < 0.05 means that the null hypothesis is false, and P ≥0.05 means that the null hypothesis is true. The correct interpretation of a P-value of 0.05 is that if the null hypothesis were indeed true, a similar or more extreme result would occur 5% of the times upon repeating the study in a similar sample. In other words, the P-value informs about the likelihood of the data given the null hypothesis and not the other way around. A possible alternative related to the P-value is the confidence interval (CI). It provides more information on the magnitude of an effect and the imprecision with which that effect was estimated. However, there is no magic bullet to replace P-values and stop erroneous interpretation of scientific results. Scientists and readers alike should make themselves familiar with the correct, nuanced interpretation of statistical tests, P-values and CIs. © The Author 2017. Published by Oxford University Press on behalf of ERA-EDTA. All rights reserved.

Functional statistics and related fields

CERN Document Server

Bongiorno, Enea; Cao, Ricardo; Vieu, Philippe

2017-01-01

This volume collects latest methodological and applied contributions on functional, high-dimensional and other complex data, related statistical models and tools as well as on operator-based statistics. It contains selected and refereed contributions presented at the Fourth International Workshop on Functional and Operatorial Statistics (IWFOS 2017) held in A Coruña, Spain, from 15 to 17 June 2017. The series of IWFOS workshops was initiated by the Working Group on Functional and Operatorial Statistics at the University of Toulouse in 2008. Since then, many of the major advances in functional statistics and related fields have been periodically presented and discussed at the IWFOS workshops. .

Understanding the Sampling Distribution and Its Use in Testing Statistical Significance.

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Breunig, Nancy A.

Despite the increasing criticism of statistical significance testing by researchers, particularly in the publication of the 1994 American Psychological Association's style manual, statistical significance test results are still popular in journal articles. For this reason, it remains important to understand the logic of inferential statistics. A…

Age-related quantitative and qualitative changes in decision making ability.

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Isella, Valeria; Mapelli, Cristina; Morielli, Nadia; Pelati, Oriana; Franceschi, Massimo; Appollonio, Ildebrando Marco

2008-01-01

The "frontal aging hypothesis" predicts that brain senescence affects predominantly the prefrontal regions. Preliminary evidence has recently been gathered in favour of an age-related change in a typically frontal process, i.e. decision making, using the Iowa Gambling Task (IGT), but overall findings have been conflicting. Following the traditional scoring method, coupled with a qualitative analysis, in the present study we compared IGT performance of 40 young (mean age: 27.9+/-4.7) and 40 old (mean age: 65.4+/-8.6) healthy adults and of 18 patients affected by frontal lobe dementia of mild severity (mean age: 65.1+/-7.4, mean MMSE score: 24.1+/-3.9). Quantitative findings support the notion that decision making ability declines with age; moreover, it approximates the impairment observed in executive dysfunction due to neurodegeneration. Results of the qualitative analysis did not reach statistical significance for the motivational and learning decision making components considered, but approached significance for the attentional component for elderly versus young normals, suggesting a possible decrease in the ability to maintain sustained attention during complex and prolonged tasks as the putative deficit underlying impaired decision making in normal aging.

Age-Related Grade Inflation Expectancies in a University Environment

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Donald A. Loffredo

2012-01-01

Full Text Available Grade inflation is a recognized problem in higher education in the United States. Age, gender, and ethnic differences in discrepancies between student reports of their expected grade in each course and their expectations for general university grading practices were explored in a survey of 166 (mostly female participants at a small upper-division university. Results revealed that while a small minority of students agreed that grading systems in college should only include A or B grades, a large majority of students expected A or B grades. Thus, student discrepancies between their expectations for grading systems and their expected class grades were in line with expectations that they should receive inflated grades. Results also revealed statistically significant age differences in grade expectation with students older than the age of 55 expecting lower grades relative to their younger counterparts.

Statistical study of the reproductive hormones in relation to age and PCOS for patients undergoing in vitro investigation in Khartoum

International Nuclear Information System (INIS)

Abdelgadir, O. M.

2002-09-01

In this study 587 Sudanese woman were studied those women were referred to gynecological clinics a infertile cases. Hormonal investigations were done for them, prolactin, (PRL). Female stimulating hormones (FSH) luotulizing hormones (LH) level were analyzed at Sudan Atomic Energy Commission (SAEC), (RIA ) lab, with the radioimmunoassay (RIA) method. The objective of this study was to find the relation between age versus hyperprolicinemia and (PCOS) polycystic ovary syndrome. Statistical analysis was done with the (SPSS) computer program. The result was 39.2% of the total patient 587 were high prolactin level hyper prolactin >370 mu/I which 10% of them were in the age between 25-30 years old. Age between 30-35 years old was found to be high frequency complain high FSH levels (>8 mu/ I) 29.1% of the patients. Found to be of high LH/FSH. Ratio which clear indication of polycystic ovary syndrome. (PCOS). (Author)

Statistical models for thermal ageing of steel materials in nuclear power plants

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Persoz, M.

1996-01-01

Some category of steel materials in nuclear power plants may be subjected to thermal ageing, whose extent depends on the steel chemical composition and the ageing parameters, i.e. temperature and duration. This ageing affects the 'impact strength' of the materials, which is a mechanical property. In order to assess the residual lifetime of these components, a probabilistic study has been launched, which takes into account the scatter over the input parameters of the mechanical model. Predictive formulae for estimating the impact strength of aged materials are important input data of the model. A data base has been created with impact strength results obtained from an ageing program in laboratory and statistical treatments have been undertaken. Two kinds of model have been developed, with non linear regression methods (PROC NLIN, available in SAS/STAT). The first one, using a hyperbolic tangent function, is partly based on physical considerations, and the second one, of an exponential type, is purely statistically built. The difficulties consist in selecting the significant parameters and attributing initial values to the coefficients, which is a requirement of the NLIN procedure. This global statistical analysis has led to general models that are unction of the chemical variables and the ageing parameters. These models are as precise (if not more) as local models that had been developed earlier for some specific values of ageing temperature and ageing duration. This paper describes the data and the methodology used to build the models and analyses the results given by the SAS system. (author)

Age-related motor unit remodeling in the Tibialis Anterior.

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Siddiqi, Ariba; Kumar, Dinesh; Arjunan, Sridhar

2015-01-01

Limited studies exist on the use of surface electromyogram (EMG) signal features to detect age-related motor unit remodeling in the Tibialis Anterior. Motor unit remodeling leads to declined muscle strength and force steadiness during submaximal contractions which are factors for risk of falls in the elderly. This study investigated the remodeling phenomena in the Tibialis Anterior using sample entropy and higher order statistics. Eighteen young (26.1 ± 2.9 years) and twelve elderly (68.7 ± 9.0 years) participants performed isometric dorsiflexion of the ankle at 20% maximal voluntary contraction (MVC) and their Tibialis Anterior (TA) EMG was recorded. Sample entropy, Gaussianity and Linearity Test statistics were calculated from the recorded EMG for each MVC. Shapiro-Wilk test was used to determine normality, and either a two-tail student t-test or Wilcoxon rank sum test was performed to determine significant difference in the EMG features between the young and old cohorts. Results show age-related motor unit remodeling to be depicted by decreased sample entropy (p <; 0.1), increased non-Gaussianity (p <; 0.05) and lesser degree of linearity in the elderly. This is due to the increased sparsity of the MUAPs as a result of the denervation-reinnervation process, and the decrease in total number of motor units.

Age-related differences in internalizing psychopathology amongst the Australian general population.

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Sunderland, Matthew; Slade, Tim; Carragher, Natacha; Batterham, Philip; Buchan, Heather

2013-11-01

Two methodological criticisms have limited the reliability and validity of findings from previous studies that seek to examine change across the life span in levels of internalizing psychopathology using general population surveys. The first criticism involves the potential influence of cohort effects that confound true age-related changes whereas the second criticism involves the use of a single form of assessment to measure and compare levels of internalizing psychopathology. This study seeks to address these criticisms by modeling age-related change using multiple measures and multiple surveys. Data from 2 epidemiological surveys conducted 10 years apart in the Australian general population were combined and used for the current study. The latent construct of internalizing psychopathology was modeled using a combination of Diagnostic and Statistical Manual of Mental Disorders (4th ed.; DSM-IV; American Psychiatric Association, 1994) depression and anxiety diagnoses as well as items from the Kessler Psychological Distress scale (K10; Kessler et al., 2002). Confirmatory factor analysis (CFA) indicated that a single internalizing dimension provided good model fit to the data. Multigroup CFA indicated that strict measurement invariance of the model can be assumed across survey administrations and age bands, justifying comparisons of mean differences in latent trait levels. Significant changes in mean levels of latent internalizing psychopathology were evident between respondents aged 30-39 years old in 1997 and respondents aged 40-49 years old in 2007, suggesting a minor but significant increase in psychopathology across middle age. By contrast, a minor but significant decrease in psychopathology was noted when transitioning from late middle age (50-59 years old) to old age (60-69 years old). The majority of individuals in the general population will experience constant levels of internalizing psychopathology as they age, suggesting that the construct is relatively

Age groups related glioblastoma study based on radiomics approach.

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Li, Zeju; Wang, Yuanyuan; Yu, Jinhua; Guo, Yi; Zhang, Qi

2017-12-01

Glioblastoma is the most aggressive malignant brain tumor with poor prognosis. Radiomics is a newly emerging and promising technique to reveal the complex relationships between high-throughput medical image features and deep information of disease including pathology, biomarkers and genomics. An approach was developed to investigate the internal relationship between magnetic resonance imaging (MRI) features and the age-related origins of glioblastomas based on a quantitative radiomics method. A fully automatic image segmentation method was applied to segment the tumor regions from three dimensional MRI images. 555 features were then extracted from the image data. By analyzing large numbers of quantitative image features, some predictive and prognostic information could be obtained by the radiomics approach. 96 patients diagnosed with glioblastoma pathologically have been divided into two age groups (age groups (T test, p age difference (T test, p= .006). In conclusion, glioblastoma in different age groups present different radiomics-feature patterns with statistical significance, which indicates that glioblastoma in different age groups should have different pathologic, protein, or genic origins.

Swiss solar power statistics 2007 - Significant expansion

International Nuclear Information System (INIS)

Hostettler, T.

2008-01-01

This article presents and discusses the 2007 statistics for solar power in Switzerland. A significant number of new installations is noted as is the high production figures from newer installations. The basics behind the compilation of the Swiss solar power statistics are briefly reviewed and an overview for the period 1989 to 2007 is presented which includes figures on the number of photovoltaic plant in service and installed peak power. Typical production figures in kilowatt-hours (kWh) per installed kilowatt-peak power (kWp) are presented and discussed for installations of various sizes. Increased production after inverter replacement in older installations is noted. Finally, the general political situation in Switzerland as far as solar power is concerned are briefly discussed as are international developments.

Test for the statistical significance of differences between ROC curves

International Nuclear Information System (INIS)

Metz, C.E.; Kronman, H.B.

1979-01-01

A test for the statistical significance of observed differences between two measured Receiver Operating Characteristic (ROC) curves has been designed and evaluated. The set of observer response data for each ROC curve is assumed to be independent and to arise from a ROC curve having a form which, in the absence of statistical fluctuations in the response data, graphs as a straight line on double normal-deviate axes. To test the significance of an apparent difference between two measured ROC curves, maximum likelihood estimates of the two parameters of each curve and the associated parameter variances and covariance are calculated from the corresponding set of observer response data. An approximate Chi-square statistic with two degrees of freedom is then constructed from the differences between the parameters estimated for each ROC curve and from the variances and covariances of these estimates. This statistic is known to be truly Chi-square distributed only in the limit of large numbers of trials in the observer performance experiments. Performance of the statistic for data arising from a limited number of experimental trials was evaluated. Independent sets of rating scale data arising from the same underlying ROC curve were paired, and the fraction of differences found (falsely) significant was compared to the significance level, α, used with the test. Although test performance was found to be somewhat dependent on both the number of trials in the data and the position of the underlying ROC curve in the ROC space, the results for various significance levels showed the test to be reliable under practical experimental conditions

Increased levels of circulating CD34+ cells in neovascular age-related macular degeneration: relation with clinical and OCT features.

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Kara, Caner; Özdal, Pınar Ç; Beyazyıldız, Emrullah; Özcan, Nurgül E; Teke, Mehmet Y; Vural, Gülden; Öztürk, Faruk

2018-01-01

To investigate the levels of circulating CD34+ stem cells in patients with neovascular type age-related macular degeneration (AMD) and its relation with clinical and optical coherence tomography (OCT) findings. The study consisted of 55 patients: 28 patients (18 male and 10 female) with neovascular type AMD as a study group and 27 patients (12 male and 15 female) scheduled for cataract surgery as a control group. The level of CD34+ stem cells was measured by flow cytometry. Demographic and clinical data were recorded. The mean ages of patients in the study and control groups were 71 ± 8 and 68 ± 6 years, respectively. There was no statistically significant difference in terms of age, sex, or systemic disease association between study and control groups. However, smoking status was significantly higher in the study group (67.9% vs 37.0%; p = 0.02). Stem cell levels were significantly higher in the study group (1.5 ± 0.9 vs 0.5 ± 0.3; p<0.001), but there was no relation between stem cell levels and clinical and OCT findings. Increased circulating CD34+ stem cell levels were observed in patients with choroidal neovascular membrane associated with AMD, but no significant relation was found between cell levels and clinical and OCT findings.

Health-related Quality of Life and Mental Health in the Process of Active and Passive Ageing.

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Dajak, Lidija; Mastilica, Miroslav; Orešković, Stjepan; Vuletić, Gorka

2016-12-01

To analyse the differences in the self-estimate of life quality depending on the ageing type - passive, active. Life-quality linked to health was measured with an SF-36 survey, which gives multi-dimensional criteria of health and life-quality. SF-36 survey represents a theoretically based and empirically proven operationalization of two overal health concepts, which are body and mental health, and its two general manifestations, functioning, and welfare. 200 examinees in total, aged from 55 to 92, were included in the research. Divided by sex, in the research participated 148 women and 52 men. Depending on the ageing way, the examinees were divided into 2 categories: passive ageing (n=100), active ageing (n=100), and for these groups a detailed result analysis was done. Statistical analysis includes descriptive statistics, Hi-square test, Spearman's correlation coefficient, and Mann-Whitney U test. In all dimensions of health, examinees from the category Active ageing achieve higher scores, which indicates better health and better functioning. Between the groups, a statistically significant difference was determined, on the following dimensions: Overall health, Pains, Energy and vitality, Social operations, and Limits due to emotional difficulties. With the Hi-square test, it was determined that there are differences between the groups. The biggest difference can be seen in the reply categories related to health deterioration (χ 2 =10.391; df=4; p=0.034). Examinees from the Active ageing group mention significantly less that their health has gotten worse compared to the previous year (26% of the active ones state that their health is somewhat worse, and only 2% that their health is significantly worse, compared to the passive ones where 36% state that their health is worse, and 9% that it's much worse compared to the year before). Tested was the difference between arithmetic middles on the issue of mental health based on the ageing type (p>0.05), and the results

Statistical analysis of biomechanical properties of the adult skull and age-related structural changes by sex in a Japanese forensic sample.

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Torimitsu, Suguru; Nishida, Yoshifumi; Takano, Tachio; Koizumi, Yoshinori; Makino, Yohsuke; Yajima, Daisuke; Hayakawa, Mutsumi; Inokuchi, Go; Motomura, Ayumi; Chiba, Fumiko; Otsuka, Katsura; Kobayashi, Kazuhiro; Odo, Yuriko; Iwase, Hirotaro

2014-01-01

The purpose of this research was to investigate the biomechanical properties of the adult human skull and the structural changes that occur with age in both sexes. The heads of 94 Japanese cadavers (54 male cadavers, 40 female cadavers) autopsied in our department were used in this research. A total of 376 cranial samples, four from each skull, were collected. Sample fracture load was measured by a bending test. A statistically significant negative correlation between the sample fracture load and cadaver age was found. This indicates that the stiffness of cranial bones in Japanese individuals decreases with age, and the risk of skull fracture thus probably increases with age. Prior to the bending test, the sample mass, the sample thickness, the ratio of the sample thickness to cadaver stature (ST/CS), and the sample density were measured and calculated. Significant negative correlations between cadaver age and sample thickness, ST/CS, and the sample density were observed only among the female samples. Computerized tomographic (CT) images of 358 cranial samples were available. The computed tomography value (CT value) of cancellous bone which refers to a quantitative scale for describing radiodensity, cancellous bone thickness and cortical bone thickness were measured and calculated. Significant negative correlation between cadaver age and the CT value or cortical bone thickness was observed only among the female samples. These findings suggest that the skull is substantially affected by decreased bone metabolism resulting from osteoporosis. Therefore, osteoporosis prevention and treatment may increase cranial stiffness and reinforce the skull structure, leading to a decrease in the risk of skull fractures. Copyright © 2013 Elsevier Ireland Ltd. All rights reserved.

Age-related differences in metabolites in the posterior cingulate cortex and hippocampus of normal ageing brain: A 1H-MRS study

International Nuclear Information System (INIS)

Reyngoudt, Harmen; Claeys, Tom; Vlerick, Leslie; Verleden, Stijn; Acou, Marjan; Deblaere, Karel; De Deene, Yves; Audenaert, Kurt; Goethals, Ingeborg; Achten, Eric

2012-01-01

Objective: To study age-related metabolic changes in N-acetylaspartate (NAA), total creatine (tCr), choline (Cho) and myo-inositol (Ins). Materials and methods: Proton magnetic resonance spectroscopy ( 1 H-MRS) was performed in the posterior cingulate cortex (PCC) and the left hippocampus (HC) of 90 healthy subjects (42 women and 48 men aged 18–76 years, mean ± SD, 48.4 ± 16.8 years). Both metabolite ratios and absolute metabolite concentrations were evaluated. Analysis of covariance (ANCOVA) and linear regression were used for statistical analysis. Results: Metabolite ratios Ins/tCr and Ins/H 2 O were found significantly increased with age in the PCC (P 2 O was only observed in the PCC (P 1 H-MRS results in these specific brain regions can be important to differentiate normal ageing from age-related pathologies such as mild cognitive impairment (MCI) and Alzheimer's disease.

Is hypertension in adult age related to unemployment at a young age? Results from the Northern Swedish Cohort.

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Nygren, Karina; Gong, Weidan; Hammarström, Anne

2015-02-01

The aim of this study was to analyse the relationship between early unemployment (ages 16-21 years) and adult hypertension after controlling for earlier hypertension, unemployment in adult life, risk factors for hypertension and confounders. A cohort of 927 (86.6% of the original cohort) 9th grade school-leavers was followed from 1981 until 2008. Data were collected through questionnaires, health examinations, and national registers. Univariate and multivariate logistic regression were used as primary statistical methods. At ages 21 and 43, hypertension was significantly more prevalent among men than women (p Unemployment between the ages of 16 and 21 was related to hypertension at age 43 among women but not men. The odds ratio (OR) was persistently high (OR 3.16 [95% confidence interval 1.45-6.89]) after controlling for late unemployment, hypertension at age 16, risk factors for hypertension and confounders. There was no significant relationship between exposure to early unemployment and hypertension at age 21 for women or men. From a public health perspective, youth unemployment is a societal problem in need of more attention and intervention in order to prevent long-term adverse health outcomes. © 2014 the Nordic Societies of Public Health.

The Impact of Supplemental Antioxidants on Visual Function in Nonadvanced Age-Related Macular Degeneration: A Head-to-Head Randomized Clinical Trial.

Science.gov (United States)

Akuffo, Kwadwo Owusu; Beatty, Stephen; Peto, Tunde; Stack, Jim; Stringham, Jim; Kelly, David; Leung, Irene; Corcoran, Laura; Nolan, John M

2017-10-01

The purpose of this study was to evaluate the impact of supplemental macular carotenoids (including versus not including meso-zeaxanthin) in combination with coantioxidants on visual function in patients with nonadvanced age-related macular degeneration. In this study, 121 participants were randomly assigned to group 1 (Age-Related Eye Disease Study 2 formulation with a low dose [25 mg] of zinc and an addition of 10 mg meso-zeaxanthin; n = 60) or group 2 (Age-Related Eye Disease Study 2 formulation with a low dose [25 mg] of zinc; n = 61). Visual function was assessed using best-corrected visual acuity, contrast sensitivity (CS), glare disability, retinal straylight, photostress recovery time, reading performance, and the National Eye Institute Visual Function Questionnaire-25. Macular pigment was measured using customized heterochromatic flicker photometry. There was a statistically significant improvement in the primary outcome measure (letter CS at 6 cycles per degree [6 cpd]) over time (P = 0.013), and this observed improvement was statistically comparable between interventions (P = 0.881). Statistically significant improvements in several secondary outcome visual function measures (letter CS at 1.2 and 2.4 cpd; mesopic and photopic CS at all spatial frequencies; mesopic glare disability at 1.5, 3, and 6 cpd; photopic glare disability at 1.5, 3, 6, and 12 cpd; photostress recovery time; retinal straylight; mean and maximum reading speed) were also observed over time (P 0.05, for all). Statistically significant increases in macular pigment at all eccentricities were observed over time (P 0.05). Antioxidant supplementation in patients with nonadvanced age-related macular degeneration results in significant increases in macular pigment and improvements in CS and other measures of visual function. (Clinical trial, http://www.isrctn.com/ISRCTN13894787).

The Age-Related Association of Movement in Irish Adolescent Youth

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Diarmuid Lester

2017-10-01

Full Text Available (1 Background: Research has shown that post-primary Irish youth are insufficiently active and fail to reach a level of proficiency across basic movement skills. The purpose of the current research was to gather cross-sectional baseline data on Irish adolescent youth, specifically the prevalence of movement skills and patterns, in order to generate an overall perspective of movement within the first three years (Junior Certificate level of post-primary education. (2 Methods: Data were collected on adolescents (N = 181; mean age: 14.42 ± 0.98 years, attending two, mixed-gender schools. Data collection included 10 fundamental movement skills (FMS and the seven tests within the Functional Movement Screen (FMS™. The data set was analysed using the Statistical Package for Social Sciences (SPSS version 20.0 for Windows. (3 Results: Overall, levels of actual mastery within fundamental and functional movement were low. There were statistically significant age-related differences observed, with a progressive decline as age increased in both the object control (p = 0.002 FMS sub-domain, and the in-line lunge (p = 0.048 test of the FMS™. (4 Conclusion: In summary, we found emerging evidence that school year group is significantly associated with mastery of movement skills and patterns. Results from the current study suggest that developing a specifically tailored movement-oriented intervention would be a strategic step towards improving the low levels of adolescent fundamental and functional movement proficiency.

OSL Age Determination of the Hearths in a Bronze Age Dwelling Site by using Bayesian Statistics

International Nuclear Information System (INIS)

Kim, Myung Jin; Yang, Hye Jin; Hong, Duk Geun

2011-01-01

OSL dating for three hearths having the sequence of use and discard in No. 29 and 29-1 dwelling sites at Sogol cultural site was carried out. Resulting from the deconvolution of natural CW-OSL decay curve and thermal zeroing test, it was turned out that OSL signal was entirely composed of the heat- and light-sensitive fast component with high photoionization cross-section and all quartz OSL signals were thermally bleached under 300 .deg. C which is the minimum temperature related to heating and cooking in Bronze age. After dose recovery test and plateau test, paleodose of each hearth sample was evaluated by using SAR method, and OSL age was determined from the ratio of paleodose to annual dose rate. For the purpose of the precision improvement of OSL age, Bayesian statistics was applied to each hearth's age and the archaeological sequence information. Finally, it could be concluded to the accurate use period of each hearth from the resultant OSL ages

OSL Age Determination of the Hearths in a Bronze Age Dwelling Site by using Bayesian Statistics

Energy Technology Data Exchange (ETDEWEB)

Kim, Myung Jin [Neosiskorea Co. Ltd., Seoul (Korea, Republic of); Yang, Hye Jin [Baekje Cultural Properties Research Institute, Gongju (Korea, Republic of); Hong, Duk Geun [Kangwon National University, Chuncheon (Korea, Republic of)

2011-06-15

OSL dating for three hearths having the sequence of use and discard in No. 29 and 29-1 dwelling sites at Sogol cultural site was carried out. Resulting from the deconvolution of natural CW-OSL decay curve and thermal zeroing test, it was turned out that OSL signal was entirely composed of the heat- and light-sensitive fast component with high photoionization cross-section and all quartz OSL signals were thermally bleached under 300 .deg. C which is the minimum temperature related to heating and cooking in Bronze age. After dose recovery test and plateau test, paleodose of each hearth sample was evaluated by using SAR method, and OSL age was determined from the ratio of paleodose to annual dose rate. For the purpose of the precision improvement of OSL age, Bayesian statistics was applied to each hearth's age and the archaeological sequence information. Finally, it could be concluded to the accurate use period of each hearth from the resultant OSL ages.

On detection and assessment of statistical significance of Genomic Islands

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Chaudhuri Probal

2008-04-01

Full Text Available Abstract Background Many of the available methods for detecting Genomic Islands (GIs in prokaryotic genomes use markers such as transposons, proximal tRNAs, flanking repeats etc., or they use other supervised techniques requiring training datasets. Most of these methods are primarily based on the biases in GC content or codon and amino acid usage of the islands. However, these methods either do not use any formal statistical test of significance or use statistical tests for which the critical values and the P-values are not adequately justified. We propose a method, which is unsupervised in nature and uses Monte-Carlo statistical tests based on randomly selected segments of a chromosome. Such tests are supported by precise statistical distribution theory, and consequently, the resulting P-values are quite reliable for making the decision. Results Our algorithm (named Design-Island, an acronym for Detection of Statistically Significant Genomic Island runs in two phases. Some 'putative GIs' are identified in the first phase, and those are refined into smaller segments containing horizontally acquired genes in the refinement phase. This method is applied to Salmonella typhi CT18 genome leading to the discovery of several new pathogenicity, antibiotic resistance and metabolic islands that were missed by earlier methods. Many of these islands contain mobile genetic elements like phage-mediated genes, transposons, integrase and IS elements confirming their horizontal acquirement. Conclusion The proposed method is based on statistical tests supported by precise distribution theory and reliable P-values along with a technique for visualizing statistically significant islands. The performance of our method is better than many other well known methods in terms of their sensitivity and accuracy, and in terms of specificity, it is comparable to other methods.

Increasing the statistical significance of entanglement detection in experiments.

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Jungnitsch, Bastian; Niekamp, Sönke; Kleinmann, Matthias; Gühne, Otfried; Lu, He; Gao, Wei-Bo; Chen, Yu-Ao; Chen, Zeng-Bing; Pan, Jian-Wei

2010-05-28

Entanglement is often verified by a violation of an inequality like a Bell inequality or an entanglement witness. Considerable effort has been devoted to the optimization of such inequalities in order to obtain a high violation. We demonstrate theoretically and experimentally that such an optimization does not necessarily lead to a better entanglement test, if the statistical error is taken into account. Theoretically, we show for different error models that reducing the violation of an inequality can improve the significance. Experimentally, we observe this phenomenon in a four-photon experiment, testing the Mermin and Ardehali inequality for different levels of noise. Furthermore, we provide a way to develop entanglement tests with high statistical significance.

Differential DNA Methylation in Relation to Age and Health Risks of Obesity

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María Luisa Mansego

2015-07-01

Full Text Available The aim of this study was to evaluate whether genome-wide levels of DNA methylation are associated with age and the health risks of obesity (HRO; defined according to BMI categories as “Low HRO” (overweight and class 1 obesity versus “High HRO” (class 2 and class 3 obesity. Anthropometric measurements were assessed in a subsample of 48 volunteers from the Metabolic Syndrome Reduction in Navarra (RESMENA study and 24 women from another independent study, Effects of Lipoic Acid and Eicosapentaenoic Acid in Human Obesity (OBEPALIP study. In the pooled population; the methylation levels of 55 CpG sites were significantly associated with age after Benjamini-Hochberg correction. In addition, DNA methylation of three CpG sites located in ELOVL2; HOXC4 and PI4KB were further negatively associated with their mRNA levels. Although no differentially methylated CpG sites were identified in relation to HRO after multiple testing correction; several nominally significant CpG sites were identified in genes related to insulin signaling; energy and lipid metabolism. Moreover, statistically significant associations between BMI or mRNA levels and two HRO-related CpG sites located in GPR133 and ITGB5 are reported. As a conclusion, these findings from two Spanish cohorts add knowledge about the important role of DNA methylation in the age-related regulation of gene expression. In addition; a relevant influence of age on DNA methylation in white blood cells was found, as well as, on a trend level, novel associations between DNA methylation and obesity.

Estimation of glandular content rate and statistical analysis of the influence of age group and compressed breast thickness on the estimated value

International Nuclear Information System (INIS)

Ohmori, Naoki; Ashida, Kenji; Fujita, Osamu

2003-01-01

Because the glandular content rate is an important factor in evaluating breast cancer detection and average glandular dose, it is important in mammography research to estimate and analyze this rate. The purpose of this study was to obtain a formula for statistical estimation of the glandular content rate, to clarify statistically the influence of age group and compressed breast thickness (CBT) on estimating the glandular content rate, and to show statistically the general relation between glandular content rate and the factors of age and CBT. The subjects were 740 Japanese women aged 20-91 years (mean±SD: 48.3±12.8 years) who had undergone mammography. In our study, the glandular content rate was statistically estimated from age group, mAs-value, and CBT when subjects underwent mammography, from a phantom simulation, and from MR images of the breast. In addition, multivariate analysis was carried to examine statistically the influence of age group and CBT on glandular content rate. The mean glandular content rate as estimated by age group was as follows: 35.6% for those in their 20s, 33.4% in the 30s, 27.5% in the 40s, 23.8% in the 50s, and 21.8% in those 60 and over. The rate for the subjects as a whole was 27.1%. This study indicated that overestimation occurred if the estimated value of the glandular content rate was not corrected in the 3D-measurement by MRI. In addition, this study showed that the statistical influence on glandular content rate was significantly larger for CBT than age. (author)

Testing the Difference of Correlated Agreement Coefficients for Statistical Significance

Science.gov (United States)

Gwet, Kilem L.

2016-01-01

This article addresses the problem of testing the difference between two correlated agreement coefficients for statistical significance. A number of authors have proposed methods for testing the difference between two correlated kappa coefficients, which require either the use of resampling methods or the use of advanced statistical modeling…

Serum Antioxidative Enzymes Levels and Oxidative Stress Products in Age-Related Cataract Patients

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Dong Chang

2013-01-01

Full Text Available Purpose. To investigate the activity of antioxidative enzymes and the products of oxidative stress in patients with age-related cataracts and compare the findings with those in healthy control subjects. Method. Sixty patients with age-related cataract and sixty healthy controls of matched age and gender were included in this study. Serum samples were obtained to detect the antioxidative enzymes of superoxide dismutase (SOD, catalase (CAT, and glutathione peroxidase (GSH-Px, and oxidation degradation products of malondialdehyde (MDA, 4-hydroxynonenal (4-HNE, conjugated diene (CD, advanced oxidation protein products (AOPP, protein carbonyl (PC, and 8-hydroxydeoxyguanosine (8-OHdG. Results. Serum SOD, GSH-Px, and CAT activities in cataract group were significantly decreased as compared to the control subjects (P<0.05. The levels of MDA, 4-HNE, and CD in cataract patients were significantly higher than those in the control subjects (P<0.05, P<0.01. Cataract patients had higher levels of 8-OHdG, AOPP, and PC with respect to the comparative group of normal subjects (P<0.01. And there was no statistical significance in concentration of antioxidative enzymes and oxidative stress products in patients with different subtype cataract. Conclusions. Oxidative stress is an important risk factor in the development of age-related cataract, and augmentation of the antioxidant defence systems may be of benefit to prevent or delay cataractogenesis.

Height, weight and BMI percentiles and nutritional status relative to the international growth references among Pakistani school-aged children

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Mushtaq Muhammad Umair

2012-03-01

Full Text Available Abstract Background Child growth is internationally recognized as an important indicator of nutritional status and health in populations. This study was aimed to compare age- and gender-specific height, weight and BMI percentiles and nutritional status relative to the international growth references among Pakistani school-aged children. Methods A population-based study was conducted with a multistage cluster sample of 1860 children aged five to twelve years in Lahore, Pakistan. Smoothed height, weight and BMI percentile curves were obtained and comparison was made with the World Health Organization 2007 (WHO and United States' Centers for Disease Control and Prevention 2000 (USCDC references. Over- and under-nutrition were defined according to the WHO and USCDC references, and the International Obesity Task Force (IOTF cut-offs. Simple descriptive statistics were used and statistical significance was considered at P Results Height, weight and BMI percentiles increased with age among both boys and girls, and both had approximately the same height and a lower weight and BMI as compared to the WHO and USCDC references. Mean differences from zero for height-, weight- and BMI-for-age z score values relative to the WHO and USCDC references were significant (P Conclusion Pakistani school-aged children significantly differed from the WHO and USCDC references. However, z score means relative to the WHO reference were closer to zero and the present study as compared to the USCDC reference. Overweight and obesity were significantly higher while underweight and thinness/wasting were significantly lower relative to the WHO reference as compared to the USCDC reference and the IOTF cut-offs. New growth charts for Pakistani children based on a nationally representative sample should be developed. Nevertheless, shifting to use of the 2007 WHO child growth reference might have important implications for child health programs and primary care pediatric clinics.

Results of Intravitreal Ranibizumab Treatment for Exudative Age-Related Macular Degeneration

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Umut Karaca

2012-01-01

Full Text Available Pur po se: To evaluate the efficacy and safety of intravitreal ranibizumab injection for exudative age-related macular degeneration. Ma te ri al and Met hod: In this study, we included forty-eight eyes of 43 age-related macular degeneration patients followed for at least twelve months. Mean age was 73.65±8.93 years and mean follow-up time was 14.2 months. All patients received three consecutive monthly intravitreal ranibizumab injections and then were followed up with clinical examination and optic coherence tomography monthly. Re-injection was executed as needed. Re sults: Twenty patients were male (46.5% and twenty-three patients were female (53.5%. The average number of ranibizumab injection was 3.7 (3-7 per eye. Twenty-six lesions (54.2% were classic (predominantly and minimally and twenty-two (45.8% were occult. Mean best-corrected visual acuity was 46.8 letters with ETDRS chart at the initial examination and 55.5 letters at twelfth month. Mean central foveal thickness decreased from 320 microns to 269 microns. There was a statistically significant improvement in visual acuity and central foveal thickness. On the other hand, this improvement was not significant between lesion types. During follow-up, there were no systemic or serious ocular complications determined. Dis cus si on: Intravitreal ranibizumab injection is safe and effective, both anatomically and functionally, for age-related macular degeneration. (Turk J Ophthalmol 2012; 42: 25-9

Age-related effects on the disposition and dosimetry of inhaled 239Pu or 144Ce in immature or aged beagle dogs

International Nuclear Information System (INIS)

Guilmette, R.A.; Boecker, B.B.; Muggenburg, B.A.; Hahn, F.F.; McClellan, R.O.

1987-01-01

Immature (90 days of age), young adult (18 months of age), and aged (8-10.5 years of age) male and female beagle dogs received a single brief pernasal inhalation exposure to an aerosol of 144 Ce in an insoluble fused aluminosilicate matrix or 239 PuO 2 . These isotopes were selected to represent low- and high-LET emitters, respectively. No age-related differences in the retention of Pu in the lungs of dogs have been observed, nor have there been any detectable differences in the uptake and retention of Pu in the tracheobronchial lymph nodes. Age-related effects have been seen in the uptake of Pu in the skeleton, with the amount of Pu being greatest in the skeleton of immature dogs. For the dogs exposed to the 144 Ce aerosol, there was a statistically significant difference in the retention of 144 Ce in the lungs of immature dogs compared to young adults. Increased uptake of 144 Ce in the immature dog skeleton was also noted. 14 refs.; 4 figs

Tremor in the Elderly: Essential and Aging-Related Tremor

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Deuschl, Günthe; Petersen, Inge; Lorenz, Delia; Christensen, Kaare

2016-01-01

Isolated tremor in the elderly is commonly diagnosed as essential tremor (ET). The prevalence of tremor increases steeply with increasing age, whereas hereditary tremor is becoming less common. Moreover, late-manifesting tremor seems to be associated with dementia and earlier mortality. We hypothesize that different entities underlie tremor in the elderly. Two thousand four hundred forty-eight subjects from the Longitudinal Study of Aging Danish Twins older than 70 y answered screening questions for ET in 2001. Two thousan fifty-six (84%) participants drew Archimedes spirals to measure their tremor severity, and classical aging phenotypes were assessed. A subgroup of 276 individuals fulfilling either screening criteria for ET or being controls were personally assessed. Medications and mortality data are available. The spiral score increased with age. The spiral score correlated with tremor severity. For the whole cohort, mortality was significantly correlated with the spiral score, and higher spiral scores were associated with lower physical and cognitive functioning. Multivariate analysis identified higher spiral scores as an independent risk factor for mortality. In contrast, the ET patients did not show an increased but rather a lower mortality rate although it was not statistically significant. Consistent with a slower than normal aging, they were also physically and cognitively better functioning than controls. Because incident tremors beyond 70 y of age show worse aging parameters and mortality than controls and ET, we propose to label it ‘aging-related tremor’ (ART). This tremor starts later in life and is accompanied by subtle signs of aging both cognitively and physically. More detailed clinical features and pathogenesis warrant further assessment. PMID:26095699

A Note on Comparing the Power of Test Statistics at Low Significance Levels.

Science.gov (United States)

Morris, Nathan; Elston, Robert

2011-01-01

It is an obvious fact that the power of a test statistic is dependent upon the significance (alpha) level at which the test is performed. It is perhaps a less obvious fact that the relative performance of two statistics in terms of power is also a function of the alpha level. Through numerous personal discussions, we have noted that even some competent statisticians have the mistaken intuition that relative power comparisons at traditional levels such as α = 0.05 will be roughly similar to relative power comparisons at very low levels, such as the level α = 5 × 10 -8 , which is commonly used in genome-wide association studies. In this brief note, we demonstrate that this notion is in fact quite wrong, especially with respect to comparing tests with differing degrees of freedom. In fact, at very low alpha levels the cost of additional degrees of freedom is often comparatively low. Thus we recommend that statisticians exercise caution when interpreting the results of power comparison studies which use alpha levels that will not be used in practice.

Statistical language learning in neonates revealed by event-related brain potentials

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Näätänen Risto

2009-03-01

Full Text Available Abstract Background Statistical learning is a candidate for one of the basic prerequisites underlying the expeditious acquisition of spoken language. Infants from 8 months of age exhibit this form of learning to segment fluent speech into distinct words. To test the statistical learning skills at birth, we recorded event-related brain responses of sleeping neonates while they were listening to a stream of syllables containing statistical cues to word boundaries. Results We found evidence that sleeping neonates are able to automatically extract statistical properties of the speech input and thus detect the word boundaries in a continuous stream of syllables containing no morphological cues. Syllable-specific event-related brain responses found in two separate studies demonstrated that the neonatal brain treated the syllables differently according to their position within pseudowords. Conclusion These results demonstrate that neonates can efficiently learn transitional probabilities or frequencies of co-occurrence between different syllables, enabling them to detect word boundaries and in this way isolate single words out of fluent natural speech. The ability to adopt statistical structures from speech may play a fundamental role as one of the earliest prerequisites of language acquisition.

Is statistical significance clinically important?--A guide to judge the clinical relevance of study findings

NARCIS (Netherlands)

Sierevelt, Inger N.; van Oldenrijk, Jakob; Poolman, Rudolf W.

2007-01-01

In this paper we describe several issues that influence the reporting of statistical significance in relation to clinical importance, since misinterpretation of p values is a common issue in orthopaedic literature. Orthopaedic research is tormented by the risks of false-positive (type I error) and

Organizational downsizing and age discrimination litigation: the influence of personnel practices and statistical evidence on litigation outcomes.

Science.gov (United States)

Wingate, Peter H; Thornton, George C; McIntyre, Kelly S; Frame, Jennifer H

2003-02-01

The present study examined relationships between reduction-in-force (RIF) personnel practices, presentation of statistical evidence, and litigation outcomes. Policy capturing methods were utilized to analyze the components of 115 federal district court opinions involving age discrimination disparate treatment allegations and organizational downsizing. Univariate analyses revealed meaningful links between RIF personnel practices, use of statistical evidence, and judicial verdict. The defendant organization was awarded summary judgment in 73% of the claims included in the study. Judicial decisions in favor of the defendant organization were found to be significantly related to such variables as formal performance appraisal systems, termination decision review within the organization, methods of employee assessment and selection for termination, and the presence of a concrete layoff policy. The use of statistical evidence in ADEA disparate treatment litigation was investigated and found to be a potentially persuasive type of indirect evidence. Legal, personnel, and evidentiary ramifications are reviewed, and a framework of downsizing mechanics emphasizing legal defensibility is presented.

Age-Related Differences of Maximum Phonation Time in Patients after Cardiac Surgery

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Kazuhiro P. Izawa

2017-12-01

Full Text Available Background and aims: Maximum phonation time (MPT, which is related to respiratory function, is widely used to evaluate maximum vocal capabilities, because its use is non-invasive, quick, and inexpensive. We aimed to examine differences in MPT by age, following recovery phase II cardiac rehabilitation (CR. Methods: This longitudinal observational study assessed 50 consecutive cardiac patients who were divided into the middle-aged group (<65 years, n = 29 and older-aged group (≥65 years, n = 21. MPTs were measured at 1 and 3 months after cardiac surgery, and were compared. Results: The duration of MPT increased more significantly from month 1 to month 3 in the middle-aged group (19.2 ± 7.8 to 27.1 ± 11.6 s, p < 0.001 than in the older-aged group (12.6 ± 3.5 to 17.9 ± 6.0 s, p < 0.001. However, no statistically significant difference occurred in the % change of MPT from 1 month to 3 months after cardiac surgery between the middle-aged group and older-aged group, respectively (41.1% vs. 42.1%. In addition, there were no significant interactions of MPT in the two groups for 1 versus 3 months (F = 1.65, p = 0.20. Conclusion: Following phase II, CR improved MPT for all cardiac surgery patients.

Age-Related Differences of Maximum Phonation Time in Patients after Cardiac Surgery.

Science.gov (United States)

Izawa, Kazuhiro P; Kasahara, Yusuke; Hiraki, Koji; Hirano, Yasuyuki; Watanabe, Satoshi

2017-12-21

Background and aims: Maximum phonation time (MPT), which is related to respiratory function, is widely used to evaluate maximum vocal capabilities, because its use is non-invasive, quick, and inexpensive. We aimed to examine differences in MPT by age, following recovery phase II cardiac rehabilitation (CR). Methods: This longitudinal observational study assessed 50 consecutive cardiac patients who were divided into the middle-aged group (<65 years, n = 29) and older-aged group (≥65 years, n = 21). MPTs were measured at 1 and 3 months after cardiac surgery, and were compared. Results: The duration of MPT increased more significantly from month 1 to month 3 in the middle-aged group (19.2 ± 7.8 to 27.1 ± 11.6 s, p < 0.001) than in the older-aged group (12.6 ± 3.5 to 17.9 ± 6.0 s, p < 0.001). However, no statistically significant difference occurred in the % change of MPT from 1 month to 3 months after cardiac surgery between the middle-aged group and older-aged group, respectively (41.1% vs. 42.1%). In addition, there were no significant interactions of MPT in the two groups for 1 versus 3 months (F = 1.65, p = 0.20). Conclusion: Following phase II, CR improved MPT for all cardiac surgery patients.

Age-related Differences in White Matter Integrity in Healthy Human Brain: Evidence from Structural Mri and Diffusion Tensor Imaging

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Rishu Rathee

2016-01-01

Full Text Available The aim is to investigate the relationship between microstructural white matter (WM diffusivity indices and macrostructural WM volume (WMV among healthy individuals (20–85 years. Whole-brain diffusion measures were calculated from diffusion tensor imaging using FMRIB software library while WMV was estimated through voxel-based morphometry, and voxel-based analysis was carried out using tract-based spatial statistics. Our results revealed that mean diffusivity, axial diffusivity, and radial diffusivity had shown good correlation with WMV but not for fractional anisotropy (FA. Voxel-wise tract-based spatial statistics analysis for FA showed a significant decrease in four regions for middle-aged group compared to young-aged group, in 22 regions for old-aged group compared to middle-aged group, and in 26 regions for old-aged group compared to young-aged group ( P < 0.05. We found significantly lower WMV, FA, and mean diffusivity values in females than males and inverted-U trend for FA in males. We conclude differential age- and gender-related changes for structural WMV and WM diffusion indices.

Statistical Significance for Hierarchical Clustering

Science.gov (United States)

Kimes, Patrick K.; Liu, Yufeng; Hayes, D. Neil; Marron, J. S.

2017-01-01

Summary Cluster analysis has proved to be an invaluable tool for the exploratory and unsupervised analysis of high dimensional datasets. Among methods for clustering, hierarchical approaches have enjoyed substantial popularity in genomics and other fields for their ability to simultaneously uncover multiple layers of clustering structure. A critical and challenging question in cluster analysis is whether the identified clusters represent important underlying structure or are artifacts of natural sampling variation. Few approaches have been proposed for addressing this problem in the context of hierarchical clustering, for which the problem is further complicated by the natural tree structure of the partition, and the multiplicity of tests required to parse the layers of nested clusters. In this paper, we propose a Monte Carlo based approach for testing statistical significance in hierarchical clustering which addresses these issues. The approach is implemented as a sequential testing procedure guaranteeing control of the family-wise error rate. Theoretical justification is provided for our approach, and its power to detect true clustering structure is illustrated through several simulation studies and applications to two cancer gene expression datasets. PMID:28099990

Association of HTRA1 rs11200638 with age-related macular degeneration (AMD) in Brazilian patients.

Science.gov (United States)

Lana, Tamires Prates; da Silva Costa, Sueli Matilde; Ananina, Galina; Hirata, Fábio Endo; Rim, Priscila Hae Hyun; Medina, Flávio MacCord; de Vasconcellos, José Paulo Cabral; de Melo, Mônica Barbosa

2018-01-01

Age-related macular degeneration is a multifactorial disease that can lead to vision impairment in older individuals. Although the etiology of age-related macular degeneration remains unknown, risk factors include age, ethnicity, smoking, hypertension, obesity, and genetic factors. Two main loci have been identified through genome-wide association studies, on chromosomes 1 and 10. Among the variants located at the 10q26 region, rs11200638, located at the HTRA1 gene promoter, has been associated with age-related macular degeneration in several populations and is considered the main polymorphism. We conducted a replication case-control study to analyze the frequency and participation of rs11200638 in the etiology of age-related macular degeneration in a sample of patients and controls from the State of São Paulo, Brazil, through polymerase chain reaction and enzymatic digestion. The frequency of the A allele was 57.60% in patients with age-related macular degeneration and 36.45% in controls (p value age-related macular degeneration group compared to the control group (p = 1.21 e-07 and 0.0357, respectively). No statistically significant results were observed after stratification in dry versus wet types or advanced versus non-advanced forms. To our knowledge, this is the first time the association between rs11200638 and overall age-related macular degeneration has been reported in South America.

Social inequalities in changes in health-related behaviour among Slovak adolescents aged between 15 and 19: A longitudinal study

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Sleskova Maria

2008-02-01

Full Text Available Abstract Background Lower socioeconomic position is generally associated with higher rates of smoking and alcohol consumption and lower levels of physical activity. Health-related behaviour is usually established during late childhood and adolescence. The aim of this study is to explore changes in health-related behaviour in a cohort of adolescents aged between 15 and 19, overall and by socioeconomic position. Methods The sample consisted of 844 first-year students (42.8% males, baseline in 1998 – mean age 14.9, follow-up in 2002 – mean age 18.8 from 31 secondary schools located in Kosice, Slovakia. This study focuses on changes in adolescents' smoking, alcohol use, experience with marijuana and lack of physical exercise with regard to their socioeconomic position. Four indicators of socioeconomic position were used – adolescents' current education level and employment status, and the highest education level and highest occupational status of their parents. We first made cross tabulations of HRB with these four indicators, using McNemar's test to assess differences. Next, we used logistic regression to assess adjusted associations, using likelihood ratio tests to assess statistical significance. Results Statistically significant increases were found in all health-related behaviours. Among males, the most obvious socioeconomic gradient was found in smoking, both at age 15 and at 19. Variations in socioeconomic differences in health-related behaviour were more apparent among females. Although at age 15, almost no socioeconomic differences in health-related behaviour were found, at age 19 differences were found for almost all socioeconomic indicators. Among males, only traditional socioeconomic gradients were found (the lower the socioeconomic position, the higher the prevalence of potentially harmful health-related behaviour, while among females reverse socioeconomic gradients were also found. Conclusion We confirmed an increase in unhealthy

A critical discussion of null hypothesis significance testing and statistical power analysis within psychological research

DEFF Research Database (Denmark)

Jones, Allan; Sommerlund, Bo

2007-01-01

The uses of null hypothesis significance testing (NHST) and statistical power analysis within psychological research are critically discussed. The article looks at the problems of relying solely on NHST when dealing with small and large sample sizes. The use of power-analysis in estimating...... the potential error introduced by small and large samples is advocated. Power analysis is not recommended as a replacement to NHST but as an additional source of information about the phenomena under investigation. Moreover, the importance of conceptual analysis in relation to statistical analysis of hypothesis...

Ocular Surface Temperature in Age-Related Macular Degeneration

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Andrea Sodi

2014-01-01

Full Text Available Background. The aim of this study is to investigate the ocular thermographic profiles in age-related macular degeneration (AMD eyes and age-matched controls to detect possible hemodynamic abnormalities, which could be involved in the pathogenesis of the disease. Methods. 32 eyes with early AMD, 37 eyes with atrophic AMD, 30 eyes affected by untreated neovascular AMD, and 43 eyes with fibrotic AMD were included. The control group consisted of 44 healthy eyes. Exclusion criteria were represented by any other ocular diseases other than AMD, tear film abnormalities, systemic cardiovascular abnormalities, diabetes mellitus, and a body temperature higher than 37.5°C. A total of 186 eyes without pupil dilation were investigated by infrared thermography (FLIR A320. The ocular surface temperature (OST of three ocular points was calculated by means of an image processing technique from the infrared images. Two-sample t-test and one-way analysis of variance (ANOVA test were used for statistical analyses. Results. ANOVA analyses showed no significant differences among AMD groups (P value >0.272. OST in AMD patients was significantly lower than in controls (P>0.05. Conclusions. Considering the possible relationship between ocular blood flow and OST, these findings might support the central role of ischemia in the pathogenesis of AMD.

Theoretical statistics of zero-age cataclysmic variables

International Nuclear Information System (INIS)

Politano, M.J.

1988-01-01

The distribution of the white dwarf masses, the distribution of the mass ratios and the distribution of the orbital periods in cataclysmic variables which are forming at the present time are calculated. These systems are referred to as zero-age cataclysmic variables. The results show that 60% of the systems being formed contain helium white dwarfs and 40% contain carbon-oxygen white dwarfs. The mean dwarf mass in those systems containing helium white dwarfs is 0.34. The mean white dwarf mass in those systems containing carbon-oxygen white dwarfs is 0.75. The orbital period distribution identifies four main classes of zero-age cataclysmic variables: (1) short-period systems containing helium white dwarfs, (2) systems containing carbon-oxygen white dwarfs whose secondaries are convectively stable against rapid mass transfer to the white dwarf, (3) systems containing carbon-oxygen white dwarfs whose secondaries are radiatively stable against rapid mass transfer to the white dwarf and (4) long period systems with evolved secondaries. The white dwarf mass distribution in zero-age cataclysmic variables has direct application to the calculation of the frequency of outburst in classical novae as a function of the mass of the white dwarf. The method developed in this thesis to calculate the distributions of the orbital parameters in zero-age cataclysmic variables can be used to calculate theoretical statistics of any class of binary systems. This method provides a theoretical framework from which to investigate the statistical properties and the evolution of the orbital parameters of binary systems

Statistical significance of trends in monthly heavy precipitation over the US

KAUST Repository

Mahajan, Salil

2011-05-11

Trends in monthly heavy precipitation, defined by a return period of one year, are assessed for statistical significance in observations and Global Climate Model (GCM) simulations over the contiguous United States using Monte Carlo non-parametric and parametric bootstrapping techniques. The results from the two Monte Carlo approaches are found to be similar to each other, and also to the traditional non-parametric Kendall\\'s τ test, implying the robustness of the approach. Two different observational data-sets are employed to test for trends in monthly heavy precipitation and are found to exhibit consistent results. Both data-sets demonstrate upward trends, one of which is found to be statistically significant at the 95% confidence level. Upward trends similar to observations are observed in some climate model simulations of the twentieth century, but their statistical significance is marginal. For projections of the twenty-first century, a statistically significant upwards trend is observed in most of the climate models analyzed. The change in the simulated precipitation variance appears to be more important in the twenty-first century projections than changes in the mean precipitation. Stochastic fluctuations of the climate-system are found to be dominate monthly heavy precipitation as some GCM simulations show a downwards trend even in the twenty-first century projections when the greenhouse gas forcings are strong. © 2011 Springer-Verlag.

Age-related changes of monoaminooxidases in rat cerebellar cortex

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FM Tranquilli Leali

2009-06-01

Full Text Available Age-related changes of the monoaminoxidases, evaluated by enzymatic staining, quantitative analysis of images, biochemical assay and statistical analysis of data were studied in cerebellar cortex of young (3-month-old and aged (26- month-old male Sprague-Dawley rats. The enzymatic staining shows the presence of monoamino-oxidases within the molecular and granular layers as well as within the Purkinje neurons of the cerebellum of young and aged animals. In molecular layer, and in Purkinje neurons the levels of monoaminooxidases were strongly increased in old rats. The granular layer showed, on the contrary, an age-dependent loss of enzymatic staining. These morphological findings were confirmed by biochemical results. The possibility that age-related changes in monoaminooxidase levels may be due to impaired energy production mechanisms and/or represent the consequence of reduced energetic needs is discussed.

Ageing and Pulse Wave Velocity in Relation to Serum Nitric Oxide

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Jyoti P. Khodnapur

2018-01-01

Full Text Available Background: The Pulse Wave Velocity (PWV is an important marker of arterial stiffness. Age related changes of arterial stiffness in relation to PWV and endothelial derived Nitric Oxide (NOx are least explored. Aim and Objectives: The present study was aimed to assess a relationship between age associated vascular stiffness and endothelial derived nitric oxide in both males and females. Materials and Methods: One hundred twenty healthy subjects male (n= 60 and female (n=60 subjects (20 to 95 years were randomly selected among general population of Vijayapur city, Karnataka. Subjects were divided into group I (20-29 years, II (30-39 years, III (40-49 years, IV (50-59 years, V (60-69 years and VI (>70 years. Physiological parameters like blood pressure and endothelial derived NOx were assessed. Vascular stiffness parameter like brachial-ankle PWV(b-aPWV and carotid femoral PWV (c-fPWV were also evaluated. Statistical analysis was done by using one way ANOVA and post hoc t test by using SPSS software. Results: Group I to group VI showed significant steady increase of b-a PWV and c-f PWV with concomitant significant decrease of serum NOx in both male and female subjects. Further a significant negative correlation between b-aPWV and c-f PWV with NOx in both male and female subjects were also observed. Conclusion: Results suggested possible influences of ageing on vascular stiffness which may be due to alteration of endothelial derived NOx.

High Resolution Topography of Age-Related Changes in Non-Rapid Eye Movement Sleep Electroencephalography.

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Kate E Sprecher

Full Text Available Sleeping brain activity reflects brain anatomy and physiology. The aim of this study was to use high density (256 channel electroencephalography (EEG during sleep to characterize topographic changes in sleep EEG power across normal aging, with high spatial resolution. Sleep was evaluated in 92 healthy adults aged 18-65 years old using full polysomnography and high density EEG. After artifact removal, spectral power density was calculated for standard frequency bands for all channels, averaged across the NREM periods of the first 3 sleep cycles. To quantify topographic changes with age, maps were generated of the Pearson's coefficient of the correlation between power and age at each electrode. Significant correlations were determined by statistical non-parametric mapping. Absolute slow wave power declined significantly with increasing age across the entire scalp, whereas declines in theta and sigma power were significant only in frontal regions. Power in fast spindle frequencies declined significantly with increasing age frontally, whereas absolute power of slow spindle frequencies showed no significant change with age. When EEG power was normalized across the scalp, a left centro-parietal region showed significantly less age-related decline in power than the rest of the scalp. This partial preservation was particularly significant in the slow wave and sigma bands. The effect of age on sleep EEG varies substantially by region and frequency band. This non-uniformity should inform the design of future investigations of aging and sleep. This study provides normative data on the effect of age on sleep EEG topography, and provides a basis from which to explore the mechanisms of normal aging as well as neurodegenerative disorders for which age is a risk factor.

The role of diabetes and aging in the determinism of hypertension and the related cerebrovascular complications.

Science.gov (United States)

Malaguarnera, Michele; Vacante, Marco; Frazzetto, Paola Mariangela; Motta, Massimo

2012-01-01

Epidemiological studies carried out on a large sample (3191 elderly and 640 centenarians) with identical criteria and applying the actual diagnostic standards, have evidenced a high, statistically significant prevalence of diabetes mellitus type 2 (DMT2) (18.84%) in the elderly, as compared to the centenarians (7.50%). This aspect is correlated with the major frequency of maturity onset diabetes in elderly (MODE), compared to the centenarians, correlated also to the mortality of diabetes mellitus (DM) of long duration. The DMT2 and the aging interact in the determinism of vascular alterations, i.e., of the hypertension, and related cardio-cerebrovascular complications. The most frequently occurring hypertension in both the elderly and centenarians was always the systolic-isolated one. The prevalence of hypertension and acute myocardial infarction (AMI) was statistically significantly higher in diabetics, compared to the normoglycemic patients, in both the elderly and the centenarians. In addition, in a group of 914 elderly patients, being diabetics or normoglycemic at the start of the studies, but having neither AMI nor stroke at the baseline studies, after 5 years, these complications were more prevalent, significantly in statistical terms, in the diabetic subjects, compared to the normoglycemic ones. The increase of life-span causes an increase of the age when the aging phenomena appear, resulting in that the equal-age elderly people today are of better clinical conditions, compared to the previous periods. The increased life span with a consequent progressive aging of the population causes a worse general clinical state of the elderly population, characterized by polypathologies, frailty, and appearance of cognitive deficits or incapabilities for performing manual or instrumental activities. Copyright © 2011 Elsevier Ireland Ltd. All rights reserved.

Age-related infra-tentorial brain atrophy on CT scan

International Nuclear Information System (INIS)

Kitani, Mitsuhiro; Kobayashi, Shotai; Yamaguchi, Shuhei; Okada, Kazunori; Murata, Akihiro; Tsunematsu, Tokugoro

1985-01-01

We had reported that the brain atrophy progressed significantly with advancing age using the two dimensional CT measurement by digitizer which was connected with personal computer. Using this method, we studied the age-related infra-tentrial brain atrophy in 67 normal subjects (14-90 years), and compared that with age-related supra-tentrial brain atrophy. There was a significant correlation between age and all indices [cranio-ventricular index (CVI), ventricular area index (VAI) and brain atrophy index (BAI)] in supratentrial brain. These indices did not correlated to the age in infra-tentrial brain (brainstem and cerebellum). Significant change of the brain atrophy occured above 60 years old was observed by BAI and VAI in supra-tentrial brain. There was a significant correlation between supra-tentrial brain atrophy index (BAI) and that of infratentrial brain. These results indicate that age-related brain atrophy might progress more slowly in brainstem and cerebellum than in cerebrum. (author)

Increasing the statistical significance of entanglement detection in experiments

Energy Technology Data Exchange (ETDEWEB)

Jungnitsch, Bastian; Niekamp, Soenke; Kleinmann, Matthias; Guehne, Otfried [Institut fuer Quantenoptik und Quanteninformation, Innsbruck (Austria); Lu, He; Gao, Wei-Bo; Chen, Zeng-Bing [Hefei National Laboratory for Physical Sciences at Microscale and Department of Modern Physics, University of Science and Technology of China, Hefei (China); Chen, Yu-Ao; Pan, Jian-Wei [Hefei National Laboratory for Physical Sciences at Microscale and Department of Modern Physics, University of Science and Technology of China, Hefei (China); Physikalisches Institut, Universitaet Heidelberg (Germany)

2010-07-01

Entanglement is often verified by a violation of an inequality like a Bell inequality or an entanglement witness. Considerable effort has been devoted to the optimization of such inequalities in order to obtain a high violation. We demonstrate theoretically and experimentally that such an optimization does not necessarily lead to a better entanglement test, if the statistical error is taken into account. Theoretically, we show for different error models that reducing the violation of an inequality can improve the significance. We show this to be the case for an error model in which the variance of an observable is interpreted as its error and for the standard error model in photonic experiments. Specifically, we demonstrate that the Mermin inequality yields a Bell test which is statistically more significant than the Ardehali inequality in the case of a photonic four-qubit state that is close to a GHZ state. Experimentally, we observe this phenomenon in a four-photon experiment, testing the above inequalities for different levels of noise.

Reporting effect sizes as a supplement to statistical significance ...

African Journals Online (AJOL)

The purpose of the article is to review the statistical significance reporting practices in reading instruction studies and to provide guidelines for when to calculate and report effect sizes in educational research. A review of six readily accessible (online) and accredited journals publishing research on reading instruction ...

Autism Spectrum Disorder in Children and Adolescents with Fragile X Syndrome: Within-Syndrome Differences and Age-Related Changes

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McDuffie, Andrea; Abbeduto, Leonard; Lewis, Pamela; Kover, Sara; Kim, Jee-Seon; Weber, Ann; Brown, W. Ted

2010-01-01

The Autism Diagnostic Interview-Revised (ADI-R) was used to examine diagnostic profiles and age-related changes in autism symptoms for a group of verbal children and adolescents who had fragile X syndrome, with and without autism. After controlling for nonverbal IQ, we found statistically significant between-group differences for lifetime and…

Your Chi-Square Test Is Statistically Significant: Now What?

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Sharpe, Donald

2015-01-01

Applied researchers have employed chi-square tests for more than one hundred years. This paper addresses the question of how one should follow a statistically significant chi-square test result in order to determine the source of that result. Four approaches were evaluated: calculating residuals, comparing cells, ransacking, and partitioning. Data…

Peripapillary Retinal Nerve Fiber Measurement with Spectral-Domain Optical Coherence Tomography in Age-Related Macular Degeneration

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Simon K. Law

2017-12-01

Full Text Available Purpose: To evaluate the relationship between the peripapillary retinal nerve fiber layer (RNFL measurements with Spectral-domain Optical Coherence Tomography (OCT and Age-related macular degeneration (AMD. Methods: Patients >60 years of age without glaucoma or record of intraocular pressure >21 mmHg and no systemic or intraocular diseases or treatment or surgical intervention that affected the RNFL underwent OCT measurement of the RNFL. The severity of AMD was staged with the Clinical Age-Related Maculopathy Staging System. The relationship between RNFL measurements and AMD stages of one eye per patient was analyzed. Results: Eighty-six eyes (46 patients with AMD and no glaucoma or other exclusion criteria received OCT RNFL measurements. Nine eyes (10.5% were excluded because of distorted peripapillary anatomy from exudative AMD (7 eyes or failure of the RNFL segmentation algorithm (2 eyes. Mean age ± S.D. of the 43 patients analyzed was 81.2 ± 7.3 years. The mean stage ± S.D. of AMD of the 77 eyes was 3.77 ± 1.05. Higher stages of AMD were statistically significantly associated with lower average RNFL and inferior sector RNFL (p = 0.049, 0 0015, respectively. The association of inferior sector RNFL and AMD stage remained statistically significant after adjusting for age. Conclusions: Spectral domain OCT is generally useful in measuring the peripapillary RNFL in eyes with different stages of AMD. Higher stage of AMD is associated with thinner peripapillary RNFL, which may masquerade as early glaucomatous damage.

Age-related disease association of endogenous γ-H2AX foci in mononuclear cells derived from leukapheresis.

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Shepherd H Schurman

Full Text Available The phosphorylated form of histone H2AX (γ-H2AX forms immunohistochemically detectable foci at DNA double strand breaks. In peripheral blood mononuclear cells (PBMCs derived from leukapheresis from patients enrolled in the Baltimore Longitudinal Study of Aging, γ-H2AX foci increased in a linear fashion with regards to age, peaking at ~57 years. The relationship between the frequency of γ-H2AX foci and age-related pathologies was assessed. We found a statistically significant (p = 0.023 50% increase in foci in PBMCs derived from patients with a known history of vitamin D deficiency. In addition, there were trends toward increased γ-H2AX foci in patients with cataracts (34% increase, p<0.10 and in sleep apnea patients (44%, p<0.10. Among patients ≥57 y/o, we found a significant (p = 0.037 36% increase in the number of γ-H2AX foci/cell for patients with hypertension compared to non-hypertensive patients. Our results support a role for increased DNA damage in the morbidity of age-related diseases. γ -H2AX may be a biomarker for human morbidity in age-related diseases.

Efficacy of vitrectomy and epiretinal membrane peeling in eyes with dry age-related macular degeneration.

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Mason, John O; Patel, Shyam A

2015-01-01

To study the efficacy of epiretinal membrane (ERM) peeling in eyes with dry age-related macular degeneration (AMD). We retrospectively analyzed patient charts on 17 eyes (16 patients) that underwent ERM peeling with a concurrent diagnosis of dry AMD. Eyes with concurrent dry AMD and with a good preoperative best-corrected visual acuity (BCVA) (better than or equal to 20/50) had a statistically significant mean BCVA improvement at 6 months after ERM peeling. There was a statistical increase in mean BCVA from 20/95 to 20/56 in dry AMD eyes, and no eyes showed worsening in BCVA at 6 months or at most recent follow-up. Five/seventeen (29.4%) eyes had cataract formation or progression. There were no other complications, reoperations, or reoccurrences. ERM peeling in eyes with dry AMD may show significant improvement, especially in eyes with good preoperative BCVA. The procedure is relatively safe with low complications and reoccurrences.

Risk assessment model for development of advanced age-related macular degeneration.

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Klein, Michael L; Francis, Peter J; Ferris, Frederick L; Hamon, Sara C; Clemons, Traci E

2011-12-01

To design a risk assessment model for development of advanced age-related macular degeneration (AMD) incorporating phenotypic, demographic, environmental, and genetic risk factors. We evaluated longitudinal data from 2846 participants in the Age-Related Eye Disease Study. At baseline, these individuals had all levels of AMD, ranging from none to unilateral advanced AMD (neovascular or geographic atrophy). Follow-up averaged 9.3 years. We performed a Cox proportional hazards analysis with demographic, environmental, phenotypic, and genetic covariates and constructed a risk assessment model for development of advanced AMD. Performance of the model was evaluated using the C statistic and the Brier score and externally validated in participants in the Complications of Age-Related Macular Degeneration Prevention Trial. The final model included the following independent variables: age, smoking history, family history of AMD (first-degree member), phenotype based on a modified Age-Related Eye Disease Study simple scale score, and genetic variants CFH Y402H and ARMS2 A69S. The model did well on performance measures, with very good discrimination (C statistic = 0.872) and excellent calibration and overall performance (Brier score at 5 years = 0.08). Successful external validation was performed, and a risk assessment tool was designed for use with or without the genetic component. We constructed a risk assessment model for development of advanced AMD. The model performed well on measures of discrimination, calibration, and overall performance and was successfully externally validated. This risk assessment tool is available for online use.

Significant Factors Related to Failed Pediatric Dental General Anesthesia Appointments at a Hospital-based Residency Program.

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Emhardt, John R; Yepes, Juan F; Vinson, LaQuia A; Jones, James E; Emhardt, John D; Kozlowski, Diana C; Eckert, George J; Maupome, Gerardo

2017-05-15

The purposes of this study were to: (1) evaluate the relationship between appointment failure and the factors of age, gender, race, insurance type, day of week, scheduled time of surgery, distance traveled, and weather; (2) investigate reasons for failure; and (3) explore the relationships between the factors and reasons for failure. Electronic medical records were accessed to obtain data for patients scheduled for dental care under general anesthesia from May 2012 to May 2015. Factors were analyzed for relation to appointment failure. Data from 3,513 appointments for 2,874 children were analyzed. Bivariate associations showed statistically significant (Pgeneral anesthesia face specific barriers to care.

Confidence intervals permit, but don't guarantee, better inference than statistical significance testing

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Melissa Coulson

2010-07-01

Full Text Available A statistically significant result, and a non-significant result may differ little, although significance status may tempt an interpretation of difference. Two studies are reported that compared interpretation of such results presented using null hypothesis significance testing (NHST, or confidence intervals (CIs. Authors of articles published in psychology, behavioural neuroscience, and medical journals were asked, via email, to interpret two fictitious studies that found similar results, one statistically significant, and the other non-significant. Responses from 330 authors varied greatly, but interpretation was generally poor, whether results were presented as CIs or using NHST. However, when interpreting CIs respondents who mentioned NHST were 60% likely to conclude, unjustifiably, the two results conflicted, whereas those who interpreted CIs without reference to NHST were 95% likely to conclude, justifiably, the two results were consistent. Findings were generally similar for all three disciplines. An email survey of academic psychologists confirmed that CIs elicit better interpretations if NHST is not invoked. Improved statistical inference can result from encouragement of meta-analytic thinking and use of CIs but, for full benefit, such highly desirable statistical reform requires also that researchers interpret CIs without recourse to NHST.

SPM analysis of cerebral blood flow changes related to age in patients with schizophrenia

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Song, Ho Chun; Kim, Sung Wan; Lee, Byeong II; Min, Jung Joon; Bom, Hee Seung

2007-01-01

The goal of this study was to explore neural activities of schizophrenic patients related to current age including the age of onset and also we examined the correlation patterns between age and neural correlates. 21 patients with schizophrenia (female/male; 10/11, mean age; 36.1 11.2) participated in this study and all patients were evaluated by criteria of DSM-IV as a schizophrenia patient. Exclusion criteria included inability to give informed consent and a history of significant neurological illness. 99mTc-ECD brain perfusion SPECT images were obtained from 21 schizophrenic patients. Using SPM (statistical parametric mapping), all images were normalized to a SPECT template (MNI template) and then smoothed. We performed an ANCOVA analysis with current age (covariate variable) and the age of onset (nuisance variable). The correlation was analyzed into positive and negative patterns. Findings are reported as a Z scores with a significance threshold of p < 0.005 (uncorrected) and a minimum cluster size of 10. Significant difference was found between current age and premorbid age (p < 0.05). Cerebral regions that were positively correlated with current age were observed in the middle frontal gyrus and the superior frontal gyrus bilaterally, the left precentral gyrus (Brodmann's area; BA 9) and the right inferior frontal gyrus (BA 46). Also, in relation to negative correlations, there were many regions in the right posterior cingulate gyrus (BA 30) and the left cuneus (BA 30), middle temporal gyrus (BA 21) and superior temporal gyrus (BA 13, 39). Additionally, the occipital regions were found in the right cuneus (BA 18) including the right middle occipital gyrus (BA 18) and right lingual gyrus (BA 19). Age effect in schizophrenic patients was observed in the dorsolateral prefrontal cortex with positive correlation. We suggest that the dorsolateral prefrontal cortex activity which is important for cognitive task performance is related to an increase of patients age

SPM analysis of cerebral blood flow changes related to age in patients with schizophrenia

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Song, Ho Chun; Kim, Sung Wan; Lee, Byeong II; Min, Jung Joon; Bom, Hee Seung [Chonnam National University Medical School, Gwangju (Korea, Republic of)

2007-07-01

The goal of this study was to explore neural activities of schizophrenic patients related to current age including the age of onset and also we examined the correlation patterns between age and neural correlates. 21 patients with schizophrenia (female/male; 10/11, mean age; 36.1 11.2) participated in this study and all patients were evaluated by criteria of DSM-IV as a schizophrenia patient. Exclusion criteria included inability to give informed consent and a history of significant neurological illness. 99mTc-ECD brain perfusion SPECT images were obtained from 21 schizophrenic patients. Using SPM (statistical parametric mapping), all images were normalized to a SPECT template (MNI template) and then smoothed. We performed an ANCOVA analysis with current age (covariate variable) and the age of onset (nuisance variable). The correlation was analyzed into positive and negative patterns. Findings are reported as a Z scores with a significance threshold of p < 0.005 (uncorrected) and a minimum cluster size of 10. Significant difference was found between current age and premorbid age (p < 0.05). Cerebral regions that were positively correlated with current age were observed in the middle frontal gyrus and the superior frontal gyrus bilaterally, the left precentral gyrus (Brodmann's area; BA 9) and the right inferior frontal gyrus (BA 46). Also, in relation to negative correlations, there were many regions in the right posterior cingulate gyrus (BA 30) and the left cuneus (BA 30), middle temporal gyrus (BA 21) and superior temporal gyrus (BA 13, 39). Additionally, the occipital regions were found in the right cuneus (BA 18) including the right middle occipital gyrus (BA 18) and right lingual gyrus (BA 19). Age effect in schizophrenic patients was observed in the dorsolateral prefrontal cortex with positive correlation. We suggest that the dorsolateral prefrontal cortex activity which is important for cognitive task performance is related to an increase of patients

Comparing the Age Related Mood Profile of Veteran Basketball Players

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Robabeh Rostami

2016-07-01

Full Text Available Background: Basketball, as an exciting team sport, is very popular among athletes with disabilities. Among psychological skills, mood states as an important variable have been of special interest to researchers. Objectives: The purpose of the present study was to investigate and compare profile of mood states (BRUMS of disabled former soldiers who play basketball in different age groups. Methodology: After getting permit to conduct the research, 28 disabled basketball players completed the demographic survey and the Brunel Mood Scale (BRUMS questionnaire. BRUMS consisted of 24 items in subscales of stress, anger, depression, fatigue, confusion and vigor. The one-way analysis of variance test was used for the data analysis. The significance level was set at P≤0.05. SPSS Statistics 22.0 was used for the analysis of data. Results: The results showed that mood states become less negative with age. However, scores showed a rising trend in the 35-39 age groups (mood of anger with P=0/02 fatigue with P=0/03 and confusion with P=0/04. Conclusion: It seems that examining the psychological variables in relation to age can help develop more effective strategies in physical and mental training programs for disabled players. Keywords: Mood States, Basketball Players, veteran with disabilities, Age

Age and gender effects on normal regional cerebral blood flow studied using two different voxel-based statistical analyses

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Pirson, A.S.; George, J.; Krug, B.; Vander Borght, T.; Van Laere, K.; Jamart, J.; D'Asseler, Y.; Minoshima, S.

2009-01-01

Fully automated analysis programs have been applied more and more to aid for the reading of regional cerebral blood flow SPECT study. They are increasingly based on the comparison of the patient study with a normal database. In this study, we evaluate the ability of Three-Dimensional Stereotactic Surface Projection (3 D-S.S.P.) to isolate effects of age and gender in a previously studied normal population. The results were also compared with those obtained using Statistical Parametric Mapping (S.P.M.99). Methods Eighty-nine 99m Tc-E.C.D.-SPECT studies performed in carefully screened healthy volunteers (46 females, 43 males; age 20 - 81 years) were analysed using 3 D-S.S.P.. A multivariate analysis based on the general linear model was performed with regions as intra-subject factor, gender as inter-subject factor and age as co-variate. Results Both age and gender had a significant interaction effect with regional tracer uptake. An age-related decline (p < 0.001) was found in the anterior cingulate gyrus, left frontal association cortex and left insula. Bilateral occipital association and left primary visual cortical uptake showed a significant relative increase with age (p < 0.001). Concerning the gender effect, women showed higher uptake (p < 0.01) in the parietal and right sensorimotor cortices. An age by gender interaction (p < 0.01) was only found in the left medial frontal cortex. The results were consistent with those obtained with S.P.M.99. Conclusion 3 D-S.S.P. analysis of normal r.C.B.F. variability is consistent with the literature and other automated voxel-based techniques, which highlight the effects of both age and gender. (authors)

Statistical Anxiety and Attitudes Towards Statistics: Development of a Comprehensive Danish Instrument

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Nielsen, Tine; Kreiner, Svend

Short abstract Motivated by experiencing with students’ psychological barriers for learning statistics we modified and extended the Statistical Anxiety Rating Scale (STARS) to develop a contemporary Danish measure of attitudes and relationship to statistics for use with higher education students...... with evidence of DIF in all cases: One TCA-item functioned differentially relative to age, one WS-item functioned differentially relative to statistics course (first or second), and two IA-items functioned differentially relative to statistics course and academic discipline (sociology, public health...

MORPHOLOGICAL STUDY OF THE AGE RELATED CHANGES OF THE CERVIX

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Monjushree Chakravarty

2016-07-01

Full Text Available BACKGROUND Disease of the cervix is a common clinical condition in females, worldwide and especially in a developing country like India. The study was undertaken in Guwahati Medical College to see the age related changes in the morphology of the cervix. AIM The study was done to observe the age related changes in the cervix and compare the same with the different studies done by the previous workers around the world so as to help clinicians to diagnose the pathologies of this part of the female reproductive system better. MATERIALS AND METHOD The specimens were divided into three groups viz. pre-reproductive, reproductive and post-menopausal. Twenty specimens were collected of each group. The results were statistically analysed and ‘t’ test was employed to find out the significant difference between the mean value. SUMMARY A study of the 60 specimens collected were done to find the morphological parameters of each group viz. pre-reproductive, reproductive and post-menopausal and the findings of each group were compared to one another and were related to the finding of previous workers. CONCLUSION The study showed that there were certain differences in the morphology of the three groups and these differences tallied with that of the previous workers.

[Quality of life in patients with age-related macular degeneration - medical and social problem].

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Muzyka-Woźniak, Maria; Misiuk-Hojło, Marta; Wesolowska, Alicja

2011-01-01

Age-related macular degeneration (AMD) is a leading cause of blindness over the age of 50 in western countries. People with AMD are suffering from serious vision-related disability and their social life is compromised. The aim of our study was to assess quality of life (QoL) in patients with exudative AMD. The study group was 100 patients treated for AMD, the control group were 30 age and sex matched subjects without ophthalmic disorders. Patients were treated with anti-VEGF therapy, by means of National Eye Institute Visual Function Questionnaire (NEI VFQ-25). As well as visual function, the NEI-VFQ investigates social functioning, mental health and dependency. There was statistically significant difference in QoL overall score between study group and control group. Patients with AMD obtained 51.1 (+/- 20.5 ) overall score, control group reached 83.7 (+/- 11.7) overall score, p = 0.001. Detailed analysis of study group revealed low acceptance of the disease and strong dependency. QoL in patients with AMD assessed with NEI VFQ-25, is significantly impaired. Low quality of life and difficulties in performing daily activities point at the need of formal psychological and social care.

The Rationale for Delaying Aging and the Prevention of Age-Related Diseases

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Nir Barzilai

2012-10-01

Full Text Available [Excerpt] We offer a different approach to delaying or preventing age-related diseases. To understand the necessity for a new approach we have plotted the mortality rates in Israelis in relation to specific age groups and diseases. With the common phenomenon of aging of Western populations it is of utmost importance to follow time-dependent and age-dependent mortality patterns to predict future needs of Western health systems. Age-specific, gender-specific, and cause-of-death-specific mortality rates were extracted from the statistical abstract of Israel1 and include data for the period of 1975–2010; these are presented in Figure 1, separately for men (A and women (B. Detailed age-specific causes of death data were available for the year 2009. Data presented were restricted to 5-year age groups starting at age 50, and for cause-specific mortality to the following age groups: 45–54, 55–64, 65–74, 75–84, and 85+. Causes of mortality were separated into malignant diseases, acute myocardial infarction, other ischemic heart diseases, other forms of heart diseases, cerebrovascular disease, diabetes mellitus, respiratory diseases, diseases of kidney, infectious diseases, all external causes, signs/symptoms and ill-defined conditions, and all other diseases. Figure 1 is similar to the one posted on the National Institute of Aging website and similar to data across the industrial world. The striking feature of this graph is that aging is a major log scale risk for most diseases, including the major killers: heart disease, cancer, diabetes, and Alzheimer’s. For example, while aging is a 100-fold risk for cardiovascular disease (CVD according to Figure 1, hypercholesterolemia is known to carry only a three-fold risk for CVD. For each of the mentioned diseases, aging is a log risk greater than the most important known risk factor for that disease.

NAD+ Deficits in Age-Related Diseases and Cancer.

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Garrido, Amanda; Djouder, Nabil

2017-08-01

The phenomenon of aging has gained widespread attention in recent times. Although significant advances have been made to better understand aging and its related pathologies including cancer, there is not yet a clear mechanism explaining why diseases and cancer are inherent parts of the aging process. Finding a unifying equation that could bridge aging and its related diseases would allow therapeutic development and solve an immense human health problem to live longer and better. In this review, we discuss NAD + reduction as the central mechanism that may connect aging to its related pathologies and cancer. NAD + boosters would ensure and ameliorate health quality during aging. Copyright © 2017 Elsevier Inc. All rights reserved.

Age-related slowing of digit symbol substitution revisited: what do longitudinal age changes reflect?

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MacDonald, Stuart W S; Hultsch, David F; Strauss, Esther; Dixon, Roger A

2003-05-01

A previous investigation reported that cross-sectional age differences in Digit Symbol Substitution (DSS) test performance reflect declines in perceptual processing speed. Support for the tenability of the processing speed hypothesis requires examining whether longitudinal age-related change in DSS performance is largely mediated by changes in speed. The present study used data from the Victoria Longitudinal Study to examine patterns and predictors of longitudinal change in DSS for 512 older adults (M(age) = 68.37 years, SD = 7.43). On the basis of multilevel modeling, baseline DSS performance was poorer for older participants and men, with longitudinal declines more pronounced with increasing age and decreasing speed. In contrast to the present cross-sectional findings, statistical control of change trajectories in perceptual speed using the same data did not substantially attenuate age changes. These discrepancies suggest different sources of variance may underlie cross-sectional age differences and longitudinal age changes for DSS.

Statistic analyses of the color experience according to the age of the observer.

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Hunjet, Anica; Parac-Osterman, Durdica; Vucaj, Edita

2013-04-01

Psychological experience of color is a real state of the communication between the environment and color, and it will depend on the source of the light, angle of the view, and particular on the observer and his health condition. Hering's theory or a theory of the opponent processes supposes that cones, which are situated in the retina of the eye, are not sensible on the three chromatic domains (areas, fields, zones) (red, green and purple-blue), but they produce a signal based on the principle of the opposed pairs of colors. A reason of this theory depends on the fact that certain disorders of the color eyesight, which include blindness to certain colors, cause blindness to pairs of opponent colors. This paper presents a demonstration of the experience of blue and yellow tone according to the age of the observer. For the testing of the statistically significant differences in the omission in the color experience according to the color of the background we use following statistical tests: Mann-Whitnney U Test, Kruskal-Wallis ANOVA and Median test. It was proven that the differences are statistically significant in the elderly persons (older than 35 years).

Analysis of Age-Related Changes in Asian Facial Skeletons Using 3D Vector Mathematics on Picture Archiving and Communication System Computed Tomography.

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Kim, Soo Jin; Kim, So Jung; Park, Jee Soo; Byun, Sung Wan; Bae, Jung Ho

2015-09-01

There are marked differences in facial skeletal characteristics between Asian and Caucasian. However, ethnic differences in age-related facial skeletal changes have not yet been fully established. The aims of this study were to evaluate age-related changes in Asian midfacial skeletons and to explore ethnic differences in facial skeletal structures with aging between Caucasian and Asian. The study included 108 men (aged 20-79 years) and 115 women (aged 20-81 years). Axial CT images with a gantry tilt angle of 0 were analyzed. We measured three-dimensional (3D) coordinates at each point with a pixel lens cursor in a picture archiving and communication system (PACS), and angles and widths between the points were calculated using 3D vector mathematics. We analyzed angular changes in 4 bony regions, including the glabellar, orbital, maxillary, and pyriform aperture regions, and changes in the orbital aperture width (distance from the posterior lacrimal crest to the frontozygomatic suture) and the pyriform width (between both upper margins of the pyriform aperture). All 4 midfacial angles in females and glabellar and maxillary angles in males showed statistically significant decreases with aging. On the other hand, the orbital and pyriform widths did not show statistically significant changes with aging. The results of this study suggest that Asian midfacial skeletons may change continuously throughout life, and that there may be significant differences in the midfacial skeleton between both sexes and between ethnic groups.

Age-related changes of structures in cerebellar cortex of cat

Indian Academy of Sciences (India)

We studied the structures of the cerebellar cortex of young adult and old cats for age-related changes, which were statistically analysed. Nissl staining was used to visualize the cortical neurons. The immunohistochemical method was used to display glial fibrillary acidic protein (GFAP)-immunoreactive (IR) astrocytes and ...

A statistical investigation of the mass discrepancy-acceleration relation

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Desmond, Harry

2017-02-01

We use the mass discrepancy-acceleration relation (the correlation between the ratio of total-to-visible mass and acceleration in galaxies; MDAR) to test the galaxy-halo connection. We analyse the MDAR using a set of 16 statistics that quantify its four most important features: shape, scatter, the presence of a `characteristic acceleration scale', and the correlation of its residuals with other galaxy properties. We construct an empirical framework for the galaxy-halo connection in LCDM to generate predictions for these statistics, starting with conventional correlations (halo abundance matching; AM) and introducing more where required. Comparing to the SPARC data, we find that: (1) the approximate shape of the MDAR is readily reproduced by AM, and there is no evidence that the acceleration at which dark matter becomes negligible has less spread in the data than in AM mocks; (2) even under conservative assumptions, AM significantly overpredicts the scatter in the relation and its normalization at low acceleration, and furthermore positions dark matter too close to galaxies' centres on average; (3) the MDAR affords 2σ evidence for an anticorrelation of galaxy size and Hubble type with halo mass or concentration at fixed stellar mass. Our analysis lays the groundwork for a bottom-up determination of the galaxy-halo connection from relations such as the MDAR, provides concrete statistical tests for specific galaxy formation models, and brings into sharper focus the relative evidence accorded by galaxy kinematics to LCDM and modified gravity alternatives.

Assessment of biochemical liver function tests in relation to age among steady state sickle cell anemia patients.

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Akuyam, S A; Abubakar, A; Lawal, N; Yusuf, R; Aminu, S M; Hassan, A; Musa, A; Bello, A K; Yahaya, I A; Okafor, P A

2017-11-01

Multiorgan failure including liver dysfunction is a common finding in sickle cell anemia (SCA) patients, the cause of which is multifactorial with advancing age said to be a major determinant. There is a paucity of data on liver function among SCA patients in relation to age in northern Nigerian hospitals, including Ahmadu Bello University Teaching Hospital (ABUTH), Zaria. This study was to assess the biochemical liver function tests (LFTs) as they relate to age among SCA patients in steady state, with a view to improving the overall monitoring of these patients. This study was carried out in ABUTH, Zaria, Northern Nigeria. LFTs were carried out in 100 SCA and 100 apparently healthy participants (controls). The SCA group was made up of fifty adults and fifty children diagnosed of SCA, whereas the control group was made up of fifty adults and fifty children who were apparently healthy and had hemoglobin AA. Paired two-tailed Student's t-test for matched samples and Pearson's linear correlation statistical methods were employed for the data analysis using Microsoft Office Excel 2007. A P ≤ 0.05 was considered as statistically significant. The serum concentrations of total bilirubin (TB), alanine transaminase (ALT), aspartate transaminase (AST), alkaline phosphatase (ALP), and AST/ALT ratio were significantly higher in SCA patients compared to the controls (P = 0.001, P = 0.001, P = 0.05, P = 0.05 and P = 0.001, respectively). Serum total protein (TP) and ALB were significantly lower (P = 0.01 and P < 0.05, respectively) in SCA patients compared with the controls. The levels of TB, ALT, AST, ALP, and AST/ALT were significantly lower in SCA adults compared to SCA children, whereas TP and ALB were higher in SCA adults compared to the SCA children. There were significant negative correlations between age and each of TB, ALT, AST, ALP, and AST/ALT, and significant positive correlations between age and each of TP and ALB in SCA patients. There are mild LFTs derangements

Age-Related Changes in Electroencephalographic Signal Complexity

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Zappasodi, Filippo; Marzetti, Laura; Olejarczyk, Elzbieta; Tecchio, Franca; Pizzella, Vittorio

2015-01-01

The study of active and healthy aging is a primary focus for social and neuroscientific communities. Here, we move a step forward in assessing electrophysiological neuronal activity changes in the brain with healthy aging. To this end, electroencephalographic (EEG) resting state activity was acquired in 40 healthy subjects (age 16–85). We evaluated Fractal Dimension (FD) according to the Higuchi algorithm, a measure which quantifies the presence of statistical similarity at different scales in temporal fluctuations of EEG signals. Our results showed that FD increases from age twenty to age fifty and then decreases. The curve that best fits the changes in FD values across age over the whole sample is a parabola, with the vertex located around age fifty. Moreover, FD changes are site specific, with interhemispheric FD asymmetry being pronounced in elderly individuals in the frontal and central regions. The present results indicate that fractal dimension well describes the modulations of brain activity with age. Since fractal dimension has been proposed to be related to the complexity of the signal dynamics, our data demonstrate that the complexity of neuronal electric activity changes across the life span of an individual, with a steady increase during young adulthood and a decrease in the elderly population. PMID:26536036

2015 QuickCompass of Sexual Assult-Related Responders: Statistical Methodology Report

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2016-02-01

Degree Age CAGE5 18 to 24 years olds 25 to 30 years olds 31 to 34 years olds 35 to 40 years olds 41 years old and older Gender CSEX Male Female...2015 QuickCompass of Sexual Assault Prevention and Response- Related Responders Statistical Methodology Report Additional copies of this report...from: http://www.dtic.mil/ Ask for report by ADA630235 DMDC Report No. 2015-039 February 2016 2015 QUICKCOMPASS OF SEXUAL ASSAULT PREVENTION

Work-related injuries: injury characteristics, survival, and age effect.

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Konstantinidis, Agathoklis; Talving, Peep; Kobayashi, Leslie; Barmparas, Galinos; Plurad, David; Lam, Lydia; Inaba, Kenji; Demetriades, Demetrios

2011-06-01

Work-related injuries impose a significant burden on society. The goal of this study was to delineate the epidemiology and the effect of age on type and mortality after occupational injuries. Patients 16 years of age or older sustaining work-related injuries were identified from the National Trauma Databank 12.0. The study population was stratified into four age groups: 16 to 35, 36 to 55, 56 to 65, and older than 65 years old. The demographic characteristics, type of injury, mechanism of injury, setting of injury, use of alcohol or other illicit drugs, and mortality were analyzed and related to age strata. Overall 67,658 patients were identified. There were 27,125 (40.1%) patients in the age group 16 to 35 years, 30,090 (44.5%) in the group 36 to 55 years, 6,618 (9.8%) in the group 56 to 65 years, and 3,825 (5.7%) older than 65 years. The injury severity increased significantly with age. Elderly patients were significantly more likely to sustain intracranial hemorrhages, spinal, and other skeletal injuries. The overall mortality was 2.9 per cent (1938) with the latter increasing significantly in a stepwise fashion with progressing age, becoming sixfold higher in patients older than 65 years (OR, 6.18; 95% CI, 4.78 to 7.80; P < 0.001). Our examination illustrates the associations between occupational injury and significant mortality that warrant intervention for mortality reduction. There is a stepwise-adjusted increase in mortality with progressing age.

Statistical significant changes in ground thermal conditions of alpine Austria during the last decade

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Kellerer-Pirklbauer, Andreas

2016-04-01

Longer data series (e.g. >10 a) of ground temperatures in alpine regions are helpful to improve the understanding regarding the effects of present climate change on distribution and thermal characteristics of seasonal frost- and permafrost-affected areas. Beginning in 2004 - and more intensively since 2006 - a permafrost and seasonal frost monitoring network was established in Central and Eastern Austria by the University of Graz. This network consists of c.60 ground temperature (surface and near-surface) monitoring sites which are located at 1922-3002 m a.s.l., at latitude 46°55'-47°22'N and at longitude 12°44'-14°41'E. These data allow conclusions about general ground thermal conditions, potential permafrost occurrence, trend during the observation period, and regional pattern of changes. Calculations and analyses of several different temperature-related parameters were accomplished. At an annual scale a region-wide statistical significant warming during the observation period was revealed by e.g. an increase in mean annual temperature values (mean, maximum) or the significant lowering of the surface frost number (F+). At a seasonal scale no significant trend of any temperature-related parameter was in most cases revealed for spring (MAM) and autumn (SON). Winter (DJF) shows only a weak warming. In contrast, the summer (JJA) season reveals in general a significant warming as confirmed by several different temperature-related parameters such as e.g. mean seasonal temperature, number of thawing degree days, number of freezing degree days, or days without night frost. On a monthly basis August shows the statistically most robust and strongest warming of all months, although regional differences occur. Despite the fact that the general ground temperature warming during the last decade is confirmed by the field data in the study region, complications in trend analyses arise by temperature anomalies (e.g. warm winter 2006/07) or substantial variations in the winter

Age-Related Patterns of Physical and Physiological Characteristics in Adolescent Wrestlers

Directory of Open Access Journals (Sweden)

Erkan Demirkan

2015-03-01

Full Text Available The aim of the study was to examine the physical and physiological differences as dependent on age of young wrestlers. One hundred and twenty-six 15 – 17 year old wrestlers volunteered as subjects in the present study. The physical and physiological profiles included body weight, height, body mass index, flexibility, anaerobic power, aerobic endurance, strength, speed, and body composition. The statistically significant (p<0.05 results are as follows: Age group 17 (AG 17 had significantly higher leg and arm anaerobic power and capacity (leg power: 952±216 Watt (W; arm power: 684±194 W and leg capacity: 489±101 W; arm capacity: 354±88 respectively as compared to the AG15 with (leg power: 718±279 Watt (W; arm power: 458±149 W and leg capacity: 376±132 W; arm capacity: 247±86 W respectively. AG17 wrestlers were significantly faster than AG 15 (4.29±.25 second - 4.53±.30 second respectively. AG 15 wrestlers had significantly lower right and left hand grip strength (right: 36.4±10.7 kg, left: 34.9±10 kg than AG 16 (right: 43.9±8.4kg, left: 42.5±7.8 kg and AG17 wrestlers (right: 46.6±8.7kg, left: 46.4±8.3 kg. In conclusion The results of this study suggest that height, body weight, fat free mass, arms – legs anaerobic power and capacity, speeds and hand grip strengths were increased both in one age range and in two ages range together with age progression, but it was clearly seen statistical differences in two ages range.

Statistical Significance and Effect Size: Two Sides of a Coin.

Science.gov (United States)

Fan, Xitao

This paper suggests that statistical significance testing and effect size are two sides of the same coin; they complement each other, but do not substitute for one another. Good research practice requires that both should be taken into consideration to make sound quantitative decisions. A Monte Carlo simulation experiment was conducted, and a…

An application of an optimal statistic for characterizing relative orientations

Science.gov (United States)

Jow, Dylan L.; Hill, Ryley; Scott, Douglas; Soler, J. D.; Martin, P. G.; Devlin, M. J.; Fissel, L. M.; Poidevin, F.

2018-02-01

We present the projected Rayleigh statistic (PRS), a modification of the classic Rayleigh statistic, as a test for non-uniform relative orientation between two pseudo-vector fields. In the application here, this gives an effective way of investigating whether polarization pseudo-vectors (spin-2 quantities) are preferentially parallel or perpendicular to filaments in the interstellar medium. For example, there are other potential applications in astrophysics, e.g. when comparing small-scale orientations with larger scale shear patterns. We compare the efficiency of the PRS against histogram binning methods that have previously been used for characterizing the relative orientations of gas column density structures with the magnetic field projected on the plane of the sky. We examine data for the Vela C molecular cloud, where the column density is inferred from Herschel submillimetre observations, and the magnetic field from observations by the Balloon-borne Large-Aperture Submillimetre Telescope in the 250-, 350- and 500-μm wavelength bands. We find that the PRS has greater statistical power than approaches that bin the relative orientation angles, as it makes more efficient use of the information contained in the data. In particular, the use of the PRS to test for preferential alignment results in a higher statistical significance, in each of the four Vela C regions, with the greatest increase being by a factor 1.3 in the South-Nest region in the 250 - μ m band.

Publication of statistically significant research findings in prosthodontics & implant dentistry in the context of other dental specialties.

Science.gov (United States)

Papageorgiou, Spyridon N; Kloukos, Dimitrios; Petridis, Haralampos; Pandis, Nikolaos

2015-10-01

To assess the hypothesis that there is excessive reporting of statistically significant studies published in prosthodontic and implantology journals, which could indicate selective publication. The last 30 issues of 9 journals in prosthodontics and implant dentistry were hand-searched for articles with statistical analyses. The percentages of significant and non-significant results were tabulated by parameter of interest. Univariable/multivariable logistic regression analyses were applied to identify possible predictors of reporting statistically significance findings. The results of this study were compared with similar studies in dentistry with random-effects meta-analyses. From the 2323 included studies 71% of them reported statistically significant results, with the significant results ranging from 47% to 86%. Multivariable modeling identified that geographical area and involvement of statistician were predictors of statistically significant results. Compared to interventional studies, the odds that in vitro and observational studies would report statistically significant results was increased by 1.20 times (OR: 2.20, 95% CI: 1.66-2.92) and 0.35 times (OR: 1.35, 95% CI: 1.05-1.73), respectively. The probability of statistically significant results from randomized controlled trials was significantly lower compared to various study designs (difference: 30%, 95% CI: 11-49%). Likewise the probability of statistically significant results in prosthodontics and implant dentistry was lower compared to other dental specialties, but this result did not reach statistical significant (P>0.05). The majority of studies identified in the fields of prosthodontics and implant dentistry presented statistically significant results. The same trend existed in publications of other specialties in dentistry. Copyright © 2015 Elsevier Ltd. All rights reserved.

Significant Statistics: Viewed with a Contextual Lens

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Tait-McCutcheon, Sandi

2010-01-01

This paper examines the pedagogical and organisational changes three lead teachers made to their statistics teaching and learning programs. The lead teachers posed the research question: What would the effect of contextually integrating statistical investigations and literacies into other curriculum areas be on student achievement? By finding the…

Age-Related Differences in Idiom Production in Adulthood

Science.gov (United States)

Conner, Peggy S.; Hyun, Jungmoon; O'Connor Wells, Barbara; Anema, Inge; Goral, Mira; Monereau-Merry, Marie-Michelle; Rubino, Daniel; Kuckuk, Raija; Obler, Loraine K.

2011-01-01

To investigate whether idiom production was vulnerable to age-related difficulties, we asked 40 younger (ages 18-30) and 40 older healthy adults (ages 60-85) to produce idiomatic expressions in a story-completion task. Younger adults produced significantly more correct idiom responses (73%) than did older adults (60%). When older adults generated…

Demonstration of statistical approaches to identify component's ageing by operational data analysis-A case study for the ageing PSA network

International Nuclear Information System (INIS)

Rodionov, Andrei; Atwood, Corwin L.; Kirchsteiger, Christian; Patrik, Milan

2008-01-01

The paper presents some results of a case study on 'Demonstration of statistical approaches to identify the component's ageing by operational data analysis', which was done in the frame of the EC JRC Ageing PSA Network. Several techniques: visual evaluation, nonparametric and parametric hypothesis tests, were proposed and applied in order to demonstrate the capacity, advantages and limitations of statistical approaches to identify the component's ageing by operational data analysis. Engineering considerations are out of the scope of the present study

"What If" Analyses: Ways to Interpret Statistical Significance Test Results Using EXCEL or "R"

Science.gov (United States)

Ozturk, Elif

2012-01-01

The present paper aims to review two motivations to conduct "what if" analyses using Excel and "R" to understand the statistical significance tests through the sample size context. "What if" analyses can be used to teach students what statistical significance tests really do and in applied research either prospectively to estimate what sample size…

Fake Statistically Valid Isotopic Ages in Impact Crater Geochronology

Science.gov (United States)

Jourdan, F.; Schmieder, M.; McWilliams, M. M.; Buchner, E.

2009-05-01

Precise dating of impact structures is crucial in several fundamental aspects, such as correlating effects on the bio- and geosphere caused by these catastrophic processes. Among the 176 listed impact structures [1], only 25 have a stated age precision better than ± 2%. Statistical investigation of these 25 ages showed that 11 ages are accurate, 12 are at best ambiguous, and 2 are not well characterized [2]. In this study, we show that even with statistically valid isotope ages, the age of an impact can be "missed" by several hundred millions of years. We present a new 40Ar/39Ar plateau age of 444 ± 4 Ma for the Acraman structure (real age ˜590 Ma [3]) and four plateau ages ranging from 81.07 ± 0.76 Ma to 74.6 ± 1.5 Ma for the Brent structure (estimated real age ˜453 Ma [4]). In addition, we discuss a 40Ar/39Ar plateau age of 994 ± 11, recently obtained by [5] on the Dhala structure (real age ˜2.0 Ga [5]). Despite careful sample preparations (single grain handpicking and HF leaching, in order to remove alteration phases), these results are much younger than the impact ages. Petrographic observations show that Acraman and Dhala grain separates all have an orange color and show evidence of alteration. This suggests that these ages are the results of hydrothermal events that triggered intensive 40Ar* loss and crystallization of secondary phases. More intriguing are the Brent samples (glassy melt rocks obtained from a drill core) that appeared very fresh under the microscope. The Brent glass might be a Cretaceous pseudotachylite generated by a late adjustment of the structure and/or by a local earthquake. Because we know the approximate age of the craters with stratigraphic evidences, these outliers are easy to identify. However, this is a red flag for any uncritical interpretation of isotopic ages (including e.g., 40Ar/39Ar, U/Pb, or U-Th/He [6]). In this paper, we encourage a multi-technique approach (i.e., isotopic, stratigraphic, paleogeographic [7,8]) and

Aspirin use and early age-related macular degeneration: a meta-analysis.

Science.gov (United States)

Kahawita, Shyalle K; Casson, Robert J

2014-02-01

The aim of this review was to evaluate the evidence for an association between Aspirin use and early age-related macular degeneration (ARMD). A literature search was performed in 5 databases with no restrictions on language or date of publication. Four studies involving 10292 individuals examining the association between aspirin and ARMD met the inclusion criteria. Meta-analysis was carried out by Cochrane Collaboration Review Manager 5.2 software (Cochrane Collaboration, Copenhagen, Denmark). The pooled odd ratios showed that Aspirin use was associated with early ARMD (pooled odds ratio 1.43, 95% CI 1.09-1.88). There is a small but statistically significant association between Aspirin use and early ARMD, which may warrant further investigation. Crown Copyright © 2014. Published by Elsevier Inc. All rights reserved.

Doubly Disadvantaged? The Relative Age Effect in Poland’s Basketball Players

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Krystian Rubajczyk, Kamil Świerzko, Andrzej Rokita

2017-06-01

Full Text Available The aim of this study was to identify the relative age effect (RAE in young Polish male (n = 3849 and female (n = 3419 basketball players aged 14 to 22 years competing in the elite games of the Polish Youth Championships. The distribution of birth dates, body height, players’ match statistics, and the results of teams participating in championships were identified. The RAE was observed in male and female group, regardless of players age. Nevertheless, the greatest disproportion in the distribution of dates of birth was found in U16 group of boys (V = 0.25, p < 0.0001. Significant differences in body height were identified in U14 and U16 groups of boys (p < 0.0001 and U14 group of girls (p < 0.01. The RAE was the most detrimental in the group of boys from teams ranked 9th or lower (p < 0.0001. The groups of male and female basketball players from the top 3 teams had the highest average body height (p < 0.001. In U14 boys, significantly higher match results and performance index ratings (PIR were observed for players born in the first half of a calendar year. The research results show the impact of the RAE on the success of youth basketball teams in Poland. The month of birth, body height and sex may determine sporting achievements in youth basketball. Coaches should consider the chronological age and pubertal growth acceleration (APHV-age at peak height velocity of players to optimize the process of identifying gifted basketball players, especially among boys of 14 years of age.

Neurological follow-up of small-for-gestational age newborn infants: a study of risk factors related to prognosis at one year of age

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José Luiz D. Gherpelli

1993-03-01

Full Text Available To examine the relative importance of some risk factors and neurological prognosis in the first year of life, 37 small-for-gestational age newborns were followed prospectively to 1 year of conceptional age. An abnormal neurological examination was found in 51.3% of the newborns and, at 12 months, 32.5% were still considered abnormal. Only 8.1% of the group had severe neurological sequelae at 1 year of corrected age. The developmental tests showed little changes during the first year, with abnormality rates varying from 16.1 to 25%. The following risk factors were analyzed concerning their relation to neurological and developmental abnormalities: high-risk pregnancy, maternal hypertension, social class, pre-term birth, neonatal asphyxia and weight and height less than 2.5 percentile at the age of 1 year. The statistical analysis showed a high correlation between subnormal weight gain and neurological (p=0.000l and developmental (p=0.001 abnormalities at 1 year. None of the other risk factors were statistically related to neurological prognosis at 1 year.

Age-related new bone formation following the use of cancellous bone-block allografts for reconstruction of atrophic alveolar ridges.

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Nissan, Joseph; Kolerman, Roni; Chaushu, Liat; Vered, Marilena; Naishlos, Sarit; Chaushu, Gavriel

2018-02-01

An age-related decrease in the number of osteogenic progenitor cells may compromise bone augmentation. Histomorphometrical assessment of age-related new bone formation, following atrophic alveolar ridge reconstruction, using cancellous bone-block allografts. Ninety-three consecutive patients (58 females and 35 males) were referred for implant-supported restoration of 122 severe atrophic alveolar ridges. Alveolar ridge deficiency locations were classified as anterior maxilla (n = 58), posterior maxilla (n= 32), and posterior mandible (n = 32). A bony deficiency of at least 3 mm horizontally and up to 3 mm vertically according to computerized tomography (CT) in the posterior mandible and anterior maxilla, served as inclusion criteria. In the posterior maxilla, a residual alveolar ridge up to 4 mm vertically according to CT served as inclusion criteria. Augmentation was performed by the use of cancellous bone-block allografts. Bone biopsies (9-month posterior maxilla, 4 months anterior maxilla and posterior mandible) of young (≤40 years) versus older (>40 years) patients were histomorphometrically evaluated. In the posterior maxilla, no statistically significant histomorphometric differences were noted. While at the anterior maxilla and posterior mandible, statistically significant more newly formed bone was found in young versus older individuals, respectively (38.6% vs 19.8%, P = 0.04 and 69% vs 31%, P = .05). New bone formation following residual alveolar ridge bone grafting is age-related. Longer bone consolidation and healing time may be recommended for older individuals. © 2017 Wiley Periodicals, Inc.

Radiographic assessment of lower third molar eruption in different anteroposterior skeletal patterns and age-related groups.

Science.gov (United States)

Jakovljevic, Aleksandar; Lazic, Emira; Soldatovic, Ivan; Nedeljkovic, Nenad; Andric, Miroslav

2015-07-01

To analyze radiographic predictors for lower third molar eruption among subjects with different anteroposterior skeletal relations and of different age groups. In total, 300 lower third molars were recorded on diagnostic digital orthopantomograms (DPTs) and lateral cephalograms (LCs). The radiographs were grouped according to sagittal intermaxillary angle (ANB), subject age, and level of lower third molar eruption. The DPT was used to analyze retromolar space, mesiodistal crown width, space/width ratio, third and second molar angulation (α, γ), third molar inclination (β), and gonion angle. The LC was used to determine ANB, angles of maxillar and mandibular prognathism (SNA, SNB), mandibular plane angle (SN/MP), and mandibular lengths. A logistic regression model was created using the statistically significant predictors. The logistic regression analysis revealed a statistically significant impact of β angle and distance between gonion and gnathion (Go-Gn) on the level of lower third molar eruption (P third molar impaction rate was significantly higher in the adult subgroup with the Class II (62.3%) compared with Class III subjects (31.7%; P third molar eruption were measured in Class III subjects. For valid estimation of mandibular third molar eruption, certain linear and angular measures (β angle, Go-Gn), as well as the size of the retromolar space, need to be considered.

Evidence of aging effects on certain safety-related components: summary and analysis

International Nuclear Information System (INIS)

1995-09-01

In response to interest shown by the Nuclear Energy Agency (NEA), Principal Working Group I (PWG- 1) of the Committee on the Safety of Nuclear Installations (CSNI) conducted a generic study on the effects of aging of active components in nuclear power plants. Representatives from France, Sweden, Finland, Japan, the United States, and the United Kingdom participated in the study by submitting reports documenting aging studies performed in their countries. This report consists of summaries of those reports, along with a comparison of the various statistical analysis methods used in the studies. The studies indicate that with some exceptions, active components generally do not present a significant aging problem in nuclear power plants. Design criteria and effective preventative maintenance programs, including timely replacement of components, are effective in mitigating potential aging problems. However, aging studies (such as qualitative and statistical analyses of failure modes and maintenance data) are an important part of efforts to identify and solve potential aging problems. Solving these problems typically includes such strategies as replacing suspect components with improved components, and implementing improved maintenance programs

Clinical significance of changes of serum osteocalcin (BGP) levels in subjects of different age-groups

International Nuclear Information System (INIS)

Jiang Lihua; Zhang Jin; Han Cuihua; Ouyang Qiaohong

2006-01-01

Objective: To investigate the changes of serum BGP levels in different age-groups. Methods: Serum BGP levels were determined with RIA in 306 subjects of different age-groups. Results: The serum BGP levels were highest in subjects of the pre-adolescent group (age5-15, n=60, vs other groups, all P 50, n=80, P<0.001). Levels in the middle age group were the lowest and were significantly lower than those in the old age group (P<0.001). No sex related differences were observed in the pre-adolescent and middle age groups, but in the youth group, serum BGP levels were significantly higher in the males than those in the females (P<0.05). However, in the old age group, the reverse was true i.e. values being significantly higher in the females (vs males, P<0.01). Conclusion: Serum BGP levels varied greatly among the different age groups. (authors)

The aging population in the twenty-first century: statistics for health policy

National Research Council Canada - National Science Library

Gilford, Dorothy M

1988-01-01

... on Statistics for an Aging Population Sam Shapiro, Chair Committee on National Statistics Commission on Behavioral and Social Sciences and Education National Research Council NATIONAL ACADEMY PRESS Washington, D.C. 1988 Copyrightoriginal retained, the be not from cannot book, paper original however, for version formatting, authoritative...

Multi-scale radiomic analysis of sub-cortical regions in MRI related to autism, gender and age

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Chaddad, Ahmad; Desrosiers, Christian; Toews, Matthew

2017-03-01

We propose using multi-scale image textures to investigate links between neuroanatomical regions and clinical variables in MRI. Texture features are derived at multiple scales of resolution based on the Laplacian-of-Gaussian (LoG) filter. Three quantifier functions (Average, Standard Deviation and Entropy) are used to summarize texture statistics within standard, automatically segmented neuroanatomical regions. Significance tests are performed to identify regional texture differences between ASD vs. TDC and male vs. female groups, as well as correlations with age (corrected p brain imaging data exchange (ABIDE) brain MRI dataset is used to evaluate texture features derived from 31 brain regions from 1112 subjects including 573 typically developing control (TDC, 99 females, 474 males) and 539 Autism spectrum disorder (ASD, 65 female and 474 male) subjects. Statistically significant texture differences between ASD vs. TDC groups are identified asymmetrically in the right hippocampus, left choroid-plexus and corpus callosum (CC), and symmetrically in the cerebellar white matter. Sex-related texture differences in TDC subjects are found in primarily in the left amygdala, left cerebellar white matter, and brain stem. Correlations between age and texture in TDC subjects are found in the thalamus-proper, caudate and pallidum, most exhibiting bilateral symmetry.

A systematic review on zinc for the prevention and treatment of age-related macular degeneration.

Science.gov (United States)

Vishwanathan, Rohini; Chung, Mei; Johnson, Elizabeth J

2013-06-12

The objective of this systematic review was to examine the evidence on zinc intake from foods and supplements in the primary prevention and treatment of AMD. Randomized controlled trials (RCTs), prospective cohort, retrospective cohort, and case-control studies that investigated zinc intake from foods and/or supplements, and AMD in men and women with a mean age of 50 years or older were included. Medline and Cochrane Central were searched from inception to February 2012 and November 2012, respectively. Data extraction and quality appraisal were done on all eligible studies. TEN STUDIES WERE INCLUDED: four RCTs, four prospective cohort, and two retrospective cohort studies. Age-related Eye Disease Study (AREDS) showed zinc treatment to significantly reduce the risk of progression to advanced AMD. The risk of visual acuity loss was of similar magnitude, but not statistically significant. Two RCTs reported statistically significant increases in visual acuity in early AMD patients and one RCT showed no effect of zinc treatment on visual acuity in advanced AMD patients. Results from six cohort studies on associations between zinc intake and incidence of AMD were inconsistent. Current evidence on zinc intake for the prevention of AMD is inconclusive. Based on the strength of AREDS, we can conclude that zinc treatment may be effective in preventing progression to advanced AMD. Zinc supplementation alone may not be sufficient to produce clinically meaningful changes in visual acuity.

Serum levels of lipid metabolites in age-related macular degeneration.

Science.gov (United States)

Orban, Tivadar; Johnson, William M; Dong, Zhiqian; Maeda, Tadao; Maeda, Akiko; Sakai, Tsutomu; Tsuneoka, Hiroshi; Mieyal, John J; Palczewski, Krzysztof

2015-11-01

Age-related macular degeneration (AMD) is a neurodegenerative disease that causes adult-onset blindness. There are 2 forms of this progressive disease: wet and dry. Currently there is no cure for AMD, but several treatment options have started to emerge making early detection critical for therapeutic success. Analysis of the eyes of Abca4(-/-)Rdh8(-/-) mice that display light-induced retinal degeneration indicates that 11-cis-retinal and docosahexaenoic acid (DHA) levels were significantly decreased as compared with the eyes of control dark-adapted C57BL/6J mice. In addition, exposure to intense light correlated with higher levels of prostaglandin G2 in the eyes of Abca4(-/-)Rdh8(-/-) mice. Intense light exposure also lowered DHA levels in the eyes of wild-type C57BL/6J mice without discernible retinal degeneration. Analysis of human serum from patients with AMD recapitulated these dysregulated DHA levels and revealed dysregulation of arachidonic acid (AA) levels as well (∼32% increase in patients with AMD compared with average levels in healthy individuals). From these observations, we then built a statistical model that included levels of DHA and AA from human serum. This model had a 74% probability of correctly identifying patients with AMD from controls. Addition of a genetic analysis for one of the most prevalent amino acid substitutions in the age-related maculopathy susceptibility 2 gene linked to AMD, Ala(69)→Ser, did not improve the statistical model. Thus, we have characterized a reliable method with the potential to detect AMD without a genetic component, paving the way for a larger-scale clinical evaluation. Our studies on mouse models along with the analysis of human serum suggest that our small molecule-based model may serve as an effective tool to estimate the risk of developing AMD. © FASEB.

Radiation-related ophthalmologic changes and aging among the atomic bomb survivors

International Nuclear Information System (INIS)

Otake, Masanori; Finch, S.C.; Choshi, Kanji; Takaku, Isao; Mishima, Hiromu; Takase, Tomoko.

1993-05-01

The relationship of ionizing radiation to the age-related ophthalmologic findings of the 1978-80 ophthalmologic examination of the atomic bomb (A-bomb) survivors of Hiroshima and Nagasaki has been reanalyzed using Dosimetry System 1986 eye organ dose estimates. The main purpose of this re-evaluation was to determine whether age and radiation exposure have an additive, synergistic, or antagonistic effect on ophthalmologic changes. The best model fitting axial opacities gives a significant positive effect for both linear dose-response and linear age-related regression coefficients and a significant negative effect for an interaction between radiation dose and age. Such a negative interaction implies an antagonistic effect in that the relative risks with relation to radiation doses decrease with increasing age. This phenomenon suggests that the lenses of younger persons are more sensitive to radiation than are those of older persons. However, the best-fitting relationship for posterior subcapsular changes suggested a linear-quadratic dose response and linear age-related effects. The quadratic estimate of radiation dose squared showed a highly significant effect with a negative trend, but the negative quadratic estimate was so extremely small it had almost no contributive value within an appropriative dose area. These data suggest an additive relationship between aging and radiation for the induction of posterior subcapsular changes, and they also indicate that there is no distinct evidence of a radiation-induced aging effect. The radiation-related relative risks increase with a log linearity. The decrease of visual acuity and accommodation with increasing age were comparable in both exposed and control subjects, with age-related visual acuity decreasing more than accommodation. (J.P.N.)

Do age-related increases in tip-of-the-tongue experiences signify episodic memory impairments?

Science.gov (United States)

Salthouse, Timothy A; Mandell, Arielle R

2013-12-01

Tip-of-the-tongue experiences (TOTs), in which a name is known but cannot be immediately retrieved from memory, can be a cause of concern if these experiences are viewed as a sign of memory decline. The current study was conducted to investigate the relation between age and TOT frequency, and the influence of episodic memory, which is the type of memory most often assessed to detect memory problems, on that relation. In a sample of adults, increased age was found to be associated with more TOTs across different types of materials, and additional analyses suggested that these relations between age and TOT frequency were not attributable to the use of different response criteria or to different amounts of knowledge. Because statistical control of a measure of episodic memory had little effect on the relation between age and TOT frequency, age-related increases in TOTs and age-related decreases in episodic memory appear to be at least partially independent phenomena.

Relation of Obesity and Menarche Age among

Directory of Open Access Journals (Sweden)

Shila Berenjy

2008-12-01

Full Text Available Objective: The aim of this study was to investigate the relation between overweight and obesity among adolescent students and age of menarche.Materials and Methods: In a cross-sectional study 399 urban adolescent girls aged 11-14 years old were selected from schools of Kermanshah city in Iran. Anthropometric examinations including, triceps skin fold (TSF, mid arm circumference (MAC, body fat percentage (BF %, were measured and information on age of menarch and student’s demographics were collected. Results: The results showed that age, body mass index (BMI and menarche age were:12.63+1.01 year, 17.71+2.94 kg/m2 and 12.16+1.18 year respectively. Prevalence of overweight in respondents was 23.2%, however; prevalence of obesity was 23.2% for 11 years old , 22.4% for12 years olds , 24% of 13 years old  and 23.5% of 14 years old. Conclusion: There was a reverse relation  between BMI and age of menarche, however; it was not significant (p>0.1. This study suggests a high prevalence of obesity and relation between BMI and anthropometric parameters in adolesent girls.

[Analysis of refractive status after cataract surgery in age-related cataract patients with shallow anterior chamber].

Science.gov (United States)

Yang, Fei; Hou, Xianru; Wu, Huijuan; Bao, Yongzhen

2014-02-01

To evaluate the characteristics of postoperative refractive status in age-related cataract patients with shallow anterior chamber and the correlation between pre-operative anterior chamber depth and postoperative refractive status. Prospective case-control study. Sixty-eight cases (90 eyes) with age-related cataract were recruited from October 2010 to January 2012 in People's Hospital Peking University including 28 cases (34 eyes) in control group and 40 cases (56 eyes) in shallow anterior chamber group according to anterior chamber depth (ACD) measured by Pentacam system. Axial length and keratometer were measured by IOL Master and intraocular lens power was calculated using SRK/T formula. Postoperative refraction, ACD and comprehensive eye examination were performed at 1 month and 3 months after cataract surgery. Using SPSS13.0 software to establish a database, the two groups were compared with independent samples t-test and correlation analysis were performed with binary logical regression. The postoperative refractive deviation at 1 month were (-0.39 ± 0.62) D in control group and (+0.73 ± 0.26) D in shallow anterior chamber group respectively which present statistical significance between the two groups (P = 0.00, t = 3.67); the postoperative refractive deviation in 3 month was (-0.37 ± 0.62) D in control group and (+0.79 ± 0.28) D in shallow anterior chamber group operatively which present statistical significance between the two groups (P = 0.00, t = 3.33). In shallow anterior chamber group, with the shallower of ACD, the greater of refractive deviation (P = 0.00, r1 month = -0.57, r3 months = -0.61). Hyperopic shift existed in age-related cataract patients with shallow anterior chamber and the shallower of ACD was, the greater of hyperopic shift happened.

Gardening and age-related weight gain: Results from a cross-sectional survey of Denver residents.

Science.gov (United States)

Litt, Jill S; Lambert, Jeffrey Richard; Glueck, Deborah H

2017-12-01

This study examined whether gardening modifies the association between age and body mass index (BMI). We used data from the Neighborhood Environments and Health Survey, which was conducted in Denver (N = 469) between 2006 and 2007. We fit two general linear mixed models. The base model had BMI in kg/m 2 as the outcome, and age, an indicator variable for non-gardening status and the age-by-non-gardening status interaction as predictors. The adjusted model included as covariates the potential confounders of education, ethnicity and self-reported health. We assessed self-selection bias and confounding. BMI was 27.18 kg/m 2 for non-gardeners, 25.62 kg/m 2 for home gardeners, and 24.17 kg/m 2 for community gardeners. In the base model, a statistically significant association was observed between age and BMI for non-gardeners but not for the combined community and home gardening group (F = 9.27, ndf = 1, ddf = 441, p = 0.0025). In the adjusted model, the association between age and BMI in non-gardeners was not statistically significant (F = 1.72, ndf = 1, ddf = 431, p = 0.1908). Gardeners differed on social and demographic factors when compared to non-gardeners. The results from the base model are consistent with the hypothesis that gardening might offset age-related weight gain. However, the cross-sectional design does not permit differentiation of true causal effects from the possible effects of bias and confounding. As a follow-up study, to remove bias and confounding, we are conducting a randomized clinical trial of community gardening in Denver.

Distinguishing between statistical significance and practical/clinical meaningfulness using statistical inference.

Science.gov (United States)

Wilkinson, Michael

2014-03-01

Decisions about support for predictions of theories in light of data are made using statistical inference. The dominant approach in sport and exercise science is the Neyman-Pearson (N-P) significance-testing approach. When applied correctly it provides a reliable procedure for making dichotomous decisions for accepting or rejecting zero-effect null hypotheses with known and controlled long-run error rates. Type I and type II error rates must be specified in advance and the latter controlled by conducting an a priori sample size calculation. The N-P approach does not provide the probability of hypotheses or indicate the strength of support for hypotheses in light of data, yet many scientists believe it does. Outcomes of analyses allow conclusions only about the existence of non-zero effects, and provide no information about the likely size of true effects or their practical/clinical value. Bayesian inference can show how much support data provide for different hypotheses, and how personal convictions should be altered in light of data, but the approach is complicated by formulating probability distributions about prior subjective estimates of population effects. A pragmatic solution is magnitude-based inference, which allows scientists to estimate the true magnitude of population effects and how likely they are to exceed an effect magnitude of practical/clinical importance, thereby integrating elements of subjective Bayesian-style thinking. While this approach is gaining acceptance, progress might be hastened if scientists appreciate the shortcomings of traditional N-P null hypothesis significance testing.

Codon Deviation Coefficient: a novel measure for estimating codon usage bias and its statistical significance

Directory of Open Access Journals (Sweden)

Zhang Zhang

2012-03-01

Full Text Available Abstract Background Genetic mutation, selective pressure for translational efficiency and accuracy, level of gene expression, and protein function through natural selection are all believed to lead to codon usage bias (CUB. Therefore, informative measurement of CUB is of fundamental importance to making inferences regarding gene function and genome evolution. However, extant measures of CUB have not fully accounted for the quantitative effect of background nucleotide composition and have not statistically evaluated the significance of CUB in sequence analysis. Results Here we propose a novel measure--Codon Deviation Coefficient (CDC--that provides an informative measurement of CUB and its statistical significance without requiring any prior knowledge. Unlike previous measures, CDC estimates CUB by accounting for background nucleotide compositions tailored to codon positions and adopts the bootstrapping to assess the statistical significance of CUB for any given sequence. We evaluate CDC by examining its effectiveness on simulated sequences and empirical data and show that CDC outperforms extant measures by achieving a more informative estimation of CUB and its statistical significance. Conclusions As validated by both simulated and empirical data, CDC provides a highly informative quantification of CUB and its statistical significance, useful for determining comparative magnitudes and patterns of biased codon usage for genes or genomes with diverse sequence compositions.

Statistics Refresher for Molecular Imaging Technologists, Part 2: Accuracy of Interpretation, Significance, and Variance.

Science.gov (United States)

Farrell, Mary Beth

2018-06-01

This article is the second part of a continuing education series reviewing basic statistics that nuclear medicine and molecular imaging technologists should understand. In this article, the statistics for evaluating interpretation accuracy, significance, and variance are discussed. Throughout the article, actual statistics are pulled from the published literature. We begin by explaining 2 methods for quantifying interpretive accuracy: interreader and intrareader reliability. Agreement among readers can be expressed simply as a percentage. However, the Cohen κ-statistic is a more robust measure of agreement that accounts for chance. The higher the κ-statistic is, the higher is the agreement between readers. When 3 or more readers are being compared, the Fleiss κ-statistic is used. Significance testing determines whether the difference between 2 conditions or interventions is meaningful. Statistical significance is usually expressed using a number called a probability ( P ) value. Calculation of P value is beyond the scope of this review. However, knowing how to interpret P values is important for understanding the scientific literature. Generally, a P value of less than 0.05 is considered significant and indicates that the results of the experiment are due to more than just chance. Variance, standard deviation (SD), confidence interval, and standard error (SE) explain the dispersion of data around a mean of a sample drawn from a population. SD is commonly reported in the literature. A small SD indicates that there is not much variation in the sample data. Many biologic measurements fall into what is referred to as a normal distribution taking the shape of a bell curve. In a normal distribution, 68% of the data will fall within 1 SD, 95% will fall within 2 SDs, and 99.7% will fall within 3 SDs. Confidence interval defines the range of possible values within which the population parameter is likely to lie and gives an idea of the precision of the statistic being

Systematic reviews of anesthesiologic interventions reported as statistically significant

DEFF Research Database (Denmark)

Imberger, Georgina; Gluud, Christian; Boylan, John

2015-01-01

statistically significant meta-analyses of anesthesiologic interventions, we used TSA to estimate power and imprecision in the context of sparse data and repeated updates. METHODS: We conducted a search to identify all systematic reviews with meta-analyses that investigated an intervention that may......: From 11,870 titles, we found 682 systematic reviews that investigated anesthesiologic interventions. In the 50 sampled meta-analyses, the median number of trials included was 8 (interquartile range [IQR], 5-14), the median number of participants was 964 (IQR, 523-1736), and the median number...

Blended learning with Moodle in medical statistics: an assessment of knowledge, attitudes and practices relating to e-learning.

Science.gov (United States)

Luo, Li; Cheng, Xiaohua; Wang, Shiyuan; Zhang, Junxue; Zhu, Wenbo; Yang, Jiaying; Liu, Pei

2017-09-19

Blended learning that combines a modular object-oriented dynamic learning environment (Moodle) with face-to-face teaching was applied to a medical statistics course to improve learning outcomes and evaluate the impact factors of students' knowledge, attitudes and practices (KAP) relating to e-learning. The same real-name questionnaire was administered before and after the intervention. The summed scores of every part (knowledge, attitude and practice) were calculated using the entropy method. A mixed linear model was fitted using the SAS PROC MIXED procedure to analyse the impact factors of KAP. Educational reform, self-perceived character, registered permanent residence and hours spent online per day were significant impact factors of e-learning knowledge. Introversion and middle type respondents' average scores were higher than those of extroversion type respondents. Regarding e-learning attitudes, educational reform, community number, Internet age and hours spent online per day had a significant impact. Specifically, participants whose Internet age was no greater than 6 years scored 7.00 points lower than those whose Internet age was greater than 10 years. Regarding e-learning behaviour, educational reform and parents' literacy had a significant impact, as the average score increased 10.05 points (P learning KAP. Additionally, this type of blended course can be implemented in many other curriculums.

Using the Bootstrap Method for a Statistical Significance Test of Differences between Summary Histograms

Science.gov (United States)

Xu, Kuan-Man

2006-01-01

A new method is proposed to compare statistical differences between summary histograms, which are the histograms summed over a large ensemble of individual histograms. It consists of choosing a distance statistic for measuring the difference between summary histograms and using a bootstrap procedure to calculate the statistical significance level. Bootstrapping is an approach to statistical inference that makes few assumptions about the underlying probability distribution that describes the data. Three distance statistics are compared in this study. They are the Euclidean distance, the Jeffries-Matusita distance and the Kuiper distance. The data used in testing the bootstrap method are satellite measurements of cloud systems called cloud objects. Each cloud object is defined as a contiguous region/patch composed of individual footprints or fields of view. A histogram of measured values over footprints is generated for each parameter of each cloud object and then summary histograms are accumulated over all individual histograms in a given cloud-object size category. The results of statistical hypothesis tests using all three distances as test statistics are generally similar, indicating the validity of the proposed method. The Euclidean distance is determined to be most suitable after comparing the statistical tests of several parameters with distinct probability distributions among three cloud-object size categories. Impacts on the statistical significance levels resulting from differences in the total lengths of satellite footprint data between two size categories are also discussed.

The relative age effect on anthropometric characteristics and motor performances in Turkish children aged between 8 and 12 years

Directory of Open Access Journals (Sweden)

Haslofça Ercan

2016-01-01

Full Text Available This study was carried out to investigate the effect of relative age on anthropometric properties and motor performance in Turkish children (girls n=423, boys n=601. Anthropometric measurement sites and techniques have been set out by the ISAK (International Society for the Advancement of Kinanthropometry. A group of tests involved in Eurofit Test Battery and other standard tests were used. For each age, the data of those who were born within the first three months and the last three months of the year were compared. The MedCalc Statistics Program was used for the differentiation and variation percentages between two periods were studied (p≤ 0.001, p= 0.05. Consequently effect of relative age was observed on anthropometric characteristics and motor performances of Turkish girls and boys between 8 and 12 years old. Researchers, trainers, families, sports managers and organizers are advised to consider Effect of Relative Age.

Age-ordered shirt numbering reduces the selection bias associated with the relative age effect.

Science.gov (United States)

Mann, David L; van Ginneken, Pleun J M A

2017-04-01

When placed into age groups for junior sporting competition, the relative differences in age between children leads to a bias in who is evaluated as being talented. While the impact of this relative age effect (RAE) is clear, until now there has been no evidence to show how to reduce it. The aim of this study was to determine whether the selection bias associated with the RAE could be reduced. Talent scouts from an elite football club watched junior games and ranked players on the basis of their potential. Scouts were allocated to one of three groups provided with contrasting information about the age of the players: (1) no age information, (2) players' birthdates or (3) knowledge that the numbers on the playing shirts corresponded to the relative age of the players. Results revealed a significant selection bias for the scouts in the no-age information group, and that bias remained when scouts knew the players' dates-of-birth. Strikingly though, the selection bias was eliminated when scouts watched the games knowing the shirt numbers corresponded to the relative ages of the players. The selection bias associated with the RAE can be reduced if information about age is presented appropriately.

Age and racial/ethnic disparities in arthritis-related hip and knee surgeries.

Science.gov (United States)

Dunlop, Dorothy D; Manheim, Larry M; Song, Jing; Sohn, Min-Woong; Feinglass, Joseph M; Chang, Huan J; Chang, Rowland W

2008-02-01

Nearly 18 million Americans experience limitations due to their arthritis. Documented disparities according to racial/ethnic groups in the use of surgical interventions such as knee and hip arthroplasty are largely based on data from Medicare beneficiaries age 65 or older. Whether there are disparities among younger adults has not been previously addressed. This study assesses age-specific racial/ethnic differences in arthritis-related knee and hip surgeries. Longitudinal (1998-2004) Health and Retirement Study. National probability sample of US community-dwelling adults. A total of 2262 black, 1292 Hispanic, and 13,159 white adults age 51 and older. The outcome is self-reported 2-year use of arthritis-related hip or knee surgery. Independent variables are demographic (race/ethnicity, age, gender), health needs (arthritis, chronic diseases, obesity, physical activity, and functional limitations), and medical access (income, wealth, education, and health insurance). Longitudinal data methods using discrete survival analysis are used to validly account for repeated (biennial) observations over time. Analyses use person-weights, stratum, and sampling error codes to provide valid inferences to the US population. Black adults under the age of 65 years report similar age/gender adjusted rates of hip/knee arthritis surgeries [hazard ratio (HR) = 1.43, 95% confidence interval (CI) = 0.87-2.38] whereas older blacks (age 65+) have significantly lower rates (HR = 0.38, CI = 0.16-0.55) compared with whites. These relationships hold controlling for health and economic differences. Both under age 65 years (HR = 0.64, CI = 0.12-1.44) and older (age 65+) Hispanic adults (HR = 0.60, CI = 0.32-1.10) report lower utilization rates, although not statistically different than whites. A large portion of the Hispanic disparity is explained by economic differences. These national data document lower rates of arthritis-related hip/knee surgeries for older black versus white adults age 65 or

P-Value, a true test of statistical significance? a cautionary note ...

African Journals Online (AJOL)

While it's not the intention of the founders of significance testing and hypothesis testing to have the two ideas intertwined as if they are complementary, the inconvenient marriage of the two practices into one coherent, convenient, incontrovertible and misinterpreted practice has dotted our standard statistics textbooks and ...

Age-related changes in normal adult pancreas: MR imaging evaluation

International Nuclear Information System (INIS)

Sato, Tomohiro; Ito, Katsuyoshi; Tamada, Tsutomu; Sone, Teruki; Noda, Yasufumi; Higaki, Atsushi; Kanki, Akihiko; Tanimoto, Daigo; Higashi, Hiroki

2012-01-01

Objective: To investigate age-related changes in normal adult pancreas as identified by magnetic resonance imaging (MRI). Materials and methods: We examined 115 patients without pancreatic diseases (21–90 years) who underwent upper abdominal MRI to evaluate the normal pancreatic MRI findings related to aging. The parameters examined were the pancreatic anteroposterior (AP) diameter, pancreatic lobulation, pancreatic signal intensity (SI), depiction of the main pancreatic duct (MPD), grade of the visual SI decrease on the opposed-phase T1-weighted images compared with in-phase images, and enhancement effect of the pancreas in the arterial phase of dynamic imaging. Results: The pancreatic AP diameter significantly reduced (head, p = 0.0172; body, p = 0.0007; tail, p < 0.0001), and lobulation (p < 0.0001) and parenchymal fatty change (p < 0.0001) became more evident with aging. No significant correlation was observed between aging and pancreatic SI, however the SI on the in-phase T1-weighted images tended to decrease with aging. No significant correlation was observed between aging and the depiction of the MPD as well as aging and contrast enhancement. Conclusion: MRI findings of pancreatic atrophy, lobulation, and fatty degeneration are characteristic changes related to aging, and it is necessary to recognize these changes in the interpretation of abdominal MRI in patients with and without pancreatic disease

A statistical method for estimating rates of soil development and ages of geologic deposits: A design for soil-chronosequence studies

Science.gov (United States)

Switzer, P.; Harden, J.W.; Mark, R.K.

1988-01-01

A statistical method for estimating rates of soil development in a given region based on calibration from a series of dated soils is used to estimate ages of soils in the same region that are not dated directly. The method is designed specifically to account for sampling procedures and uncertainties that are inherent in soil studies. Soil variation and measurement error, uncertainties in calibration dates and their relation to the age of the soil, and the limited number of dated soils are all considered. Maximum likelihood (ML) is employed to estimate a parametric linear calibration curve, relating soil development to time or age on suitably transformed scales. Soil variation on a geomorphic surface of a certain age is characterized by replicate sampling of soils on each surface; such variation is assumed to have a Gaussian distribution. The age of a geomorphic surface is described by older and younger bounds. This technique allows age uncertainty to be characterized by either a Gaussian distribution or by a triangular distribution using minimum, best-estimate, and maximum ages. The calibration curve is taken to be linear after suitable (in certain cases logarithmic) transformations, if required, of the soil parameter and age variables. Soil variability, measurement error, and departures from linearity are described in a combined fashion using Gaussian distributions with variances particular to each sampled geomorphic surface and the number of sample replicates. Uncertainty in age of a geomorphic surface used for calibration is described using three parameters by one of two methods. In the first method, upper and lower ages are specified together with a coverage probability; this specification is converted to a Gaussian distribution with the appropriate mean and variance. In the second method, "absolute" older and younger ages are specified together with a most probable age; this specification is converted to an asymmetric triangular distribution with mode at the

Codon Deviation Coefficient: A novel measure for estimating codon usage bias and its statistical significance

KAUST Repository

Zhang, Zhang

2012-03-22

Background: Genetic mutation, selective pressure for translational efficiency and accuracy, level of gene expression, and protein function through natural selection are all believed to lead to codon usage bias (CUB). Therefore, informative measurement of CUB is of fundamental importance to making inferences regarding gene function and genome evolution. However, extant measures of CUB have not fully accounted for the quantitative effect of background nucleotide composition and have not statistically evaluated the significance of CUB in sequence analysis.Results: Here we propose a novel measure--Codon Deviation Coefficient (CDC)--that provides an informative measurement of CUB and its statistical significance without requiring any prior knowledge. Unlike previous measures, CDC estimates CUB by accounting for background nucleotide compositions tailored to codon positions and adopts the bootstrapping to assess the statistical significance of CUB for any given sequence. We evaluate CDC by examining its effectiveness on simulated sequences and empirical data and show that CDC outperforms extant measures by achieving a more informative estimation of CUB and its statistical significance.Conclusions: As validated by both simulated and empirical data, CDC provides a highly informative quantification of CUB and its statistical significance, useful for determining comparative magnitudes and patterns of biased codon usage for genes or genomes with diverse sequence compositions. 2012 Zhang et al; licensee BioMed Central Ltd.

Assessing Statistically Significant Heavy-Metal Concentrations in Abandoned Mine Areas via Hot Spot Analysis of Portable XRF Data.

Science.gov (United States)

Kim, Sung-Min; Choi, Yosoon

2017-06-18

To develop appropriate measures to prevent soil contamination in abandoned mining areas, an understanding of the spatial variation of the potentially toxic trace elements (PTEs) in the soil is necessary. For the purpose of effective soil sampling, this study uses hot spot analysis, which calculates a z -score based on the Getis-Ord Gi* statistic to identify a statistically significant hot spot sample. To constitute a statistically significant hot spot, a feature with a high value should also be surrounded by other features with high values. Using relatively cost- and time-effective portable X-ray fluorescence (PXRF) analysis, sufficient input data are acquired from the Busan abandoned mine and used for hot spot analysis. To calibrate the PXRF data, which have a relatively low accuracy, the PXRF analysis data are transformed using the inductively coupled plasma atomic emission spectrometry (ICP-AES) data. The transformed PXRF data of the Busan abandoned mine are classified into four groups according to their normalized content and z -scores: high content with a high z -score (HH), high content with a low z -score (HL), low content with a high z -score (LH), and low content with a low z -score (LL). The HL and LH cases may be due to measurement errors. Additional or complementary surveys are required for the areas surrounding these suspect samples or for significant hot spot areas. The soil sampling is conducted according to a four-phase procedure in which the hot spot analysis and proposed group classification method are employed to support the development of a sampling plan for the following phase. Overall, 30, 50, 80, and 100 samples are investigated and analyzed in phases 1-4, respectively. The method implemented in this case study may be utilized in the field for the assessment of statistically significant soil contamination and the identification of areas for which an additional survey is required.

Assessing Statistically Significant Heavy-Metal Concentrations in Abandoned Mine Areas via Hot Spot Analysis of Portable XRF Data

Directory of Open Access Journals (Sweden)

Sung-Min Kim

2017-06-01

Full Text Available To develop appropriate measures to prevent soil contamination in abandoned mining areas, an understanding of the spatial variation of the potentially toxic trace elements (PTEs in the soil is necessary. For the purpose of effective soil sampling, this study uses hot spot analysis, which calculates a z-score based on the Getis-Ord Gi* statistic to identify a statistically significant hot spot sample. To constitute a statistically significant hot spot, a feature with a high value should also be surrounded by other features with high values. Using relatively cost- and time-effective portable X-ray fluorescence (PXRF analysis, sufficient input data are acquired from the Busan abandoned mine and used for hot spot analysis. To calibrate the PXRF data, which have a relatively low accuracy, the PXRF analysis data are transformed using the inductively coupled plasma atomic emission spectrometry (ICP-AES data. The transformed PXRF data of the Busan abandoned mine are classified into four groups according to their normalized content and z-scores: high content with a high z-score (HH, high content with a low z-score (HL, low content with a high z-score (LH, and low content with a low z-score (LL. The HL and LH cases may be due to measurement errors. Additional or complementary surveys are required for the areas surrounding these suspect samples or for significant hot spot areas. The soil sampling is conducted according to a four-phase procedure in which the hot spot analysis and proposed group classification method are employed to support the development of a sampling plan for the following phase. Overall, 30, 50, 80, and 100 samples are investigated and analyzed in phases 1–4, respectively. The method implemented in this case study may be utilized in the field for the assessment of statistically significant soil contamination and the identification of areas for which an additional survey is required.

Evolutionary significance of ageing in the wild.

Science.gov (United States)

Kowald, Axel; Kirkwood, Thomas B L

2015-11-01

Human lifespan has risen dramatically over the last 150 years, leading to a significant increase in the fraction of aged people in the population. Until recently it was believed that this contrasted strongly with the situation in wild populations of animals, where the likelihood of encountering demonstrably senescent individuals was believed to be negligible. Over the recent years, however, a series of field studies has appeared that shows ageing can also be observed for many species in the wild. We discuss here the relevance of this finding for the different evolutionary theories of ageing, since it has been claimed that ageing in the wild is incompatible with the so-called non-adaptive (non-programmed) theories, i.e. those in which ageing is presumed not to offer a direct selection benefit. We show that a certain proportion of aged individuals in the population is fully compatible with the antagonistic pleiotropy and the disposable soma theories, while it is difficult to reconcile with the mutation accumulation theory. We also quantify the costs of ageing using life history data from recent field studies and a range of possible metrics. We discuss the merits and problems of the different metrics and also introduce a new metric, yearly death toll, that aims directly at quantifying the deaths caused by the ageing process. Copyright © 2015 Elsevier Inc. All rights reserved.

Parental age in relation to severity of clefting

DEFF Research Database (Denmark)

Hermann, Nuno Vibe; Darvann, Tron Andre; Kreiborg, Sven

2016-01-01

Lip and/or Palate (IC). Wilcoxon Rank-Sum test (5% significance level) was applied in order to test for group differences. Standard logistic regression was used in order to estimate the risk of developing CC relative to IC. Results. In the group with CC mean paternal age was 29.5+/-4.5 (1SD) years...... parental ages in the group with IC did not differ from normative population values during the same time period. Logistic regression showed for paternal age OR=1.1[1.04,1.16](Wald confidence limits); for maternal age 1.08[1.01,1.15]. Conclusions. The hypothesis was rejected. Parental age was significantly...... of cleft individuals, as well as to compare parental age in the cleft population with normative values of parental age. It was hypothesized that there was no difference in parental age between the cleft groups with incomplete and complete clefts, respectively. Methods/Descriptions. The consecutive non...

Age-related hearing loss

Science.gov (United States)

... grow older. Your genes and loud noise (from rock concerts or music headphones) may play a large role. The following factors contribute to age-related hearing loss: Family history (age-related hearing loss tends to run in ...

Prognostic Factors of Early Morphological Response to Treatment with Ranibizumab in Patients with Wet Age-Related Macular Degeneration

Directory of Open Access Journals (Sweden)

Oldřich Chrapek

2015-01-01

Full Text Available Aim. To assess the significance of age, gender, baseline best corrected visual acuity, baseline macula thickness, and type and size of choroidal neovascularization in early morphological therapeutic response to ranibizumab treatment in patients with the wet form of age-related macular degeneration. Methods. From 09/2008 to 06/2013 we evaluated 1153 newly diagnosed, treatment-naïve patients treated with ranibizumab. Based on the morphological findings in the macula following the initial 3 injections of ranibizumab, the patients were divided into two groups based on active and inactive choroidal neovascularization. Results. After the initial 3 injections of ranibizumab, we examined the sample of 841 eyes with active CNV and 312 eyes with inactive CNV. In the inactive group, we found a statistically higher proportion of occult CNV (P<0.001 and lower incidence of CNV greater than 5DA (P < 0.001 compared with the active group. We found no statistically significant difference in age, gender, baseline best corrected visual acuity, or baseline macula thickness between the inactive and active groups. Conclusion. Occult CNV and CNV smaller than 5DA are optimistic factors for a better morphological therapeutic response at the beginning of ranibizumab treatment.

Statistical behavior and geological significance of the geochemical distribution of trace elements in the Cretaceous volcanics Cordoba and San Luis, Argentina

International Nuclear Information System (INIS)

Daziano, C.

2010-01-01

Statistical analysis of trace elements in volcanics research s, allowed to distinguish two independent populations with the same geochemical environment. For each component they have variable index of homogeneity resulting in dissimilar average values that reveal geochemical intra telluric phenomena. On the other hand the inhomogeneities observed in these rocks - as reflected in its petrochemical characters - could be exacerbated especially at so remote and dispersed location of their pitches, their relations with the enclosing rocks for the ranges of compositional variation, due differences relative ages

Interpreting Statistical Significance Test Results: A Proposed New "What If" Method.

Science.gov (United States)

Kieffer, Kevin M.; Thompson, Bruce

As the 1994 publication manual of the American Psychological Association emphasized, "p" values are affected by sample size. As a result, it can be helpful to interpret the results of statistical significant tests in a sample size context by conducting so-called "what if" analyses. However, these methods can be inaccurate…

Molecular Diagnostics of Ageing and Tackling Age-related Disease.

Science.gov (United States)

Timmons, James A

2017-01-01

As average life expectancy increases there is a greater focus on health-span and, in particular, how to treat or prevent chronic age-associated diseases. Therapies which were able to control 'biological age' with the aim of postponing chronic and costly diseases of old age require an entirely new approach to drug development. Molecular technologies and machine-learning methods have already yielded diagnostics that help guide cancer treatment and cardiovascular procedures. Discovery of valid and clinically informative diagnostics of human biological age (combined with disease-specific biomarkers) has the potential to alter current drug-discovery strategies, aid clinical trial recruitment and maximize healthy ageing. I will review some basic principles that govern the development of 'ageing' diagnostics, how such assays could be used during the drug-discovery or development process. Important logistical and statistical considerations are illustrated by reviewing recent biomarker activity in the field of Alzheimer's disease, as dementia represents the most pressing of priorities for the pharmaceutical industry, as well as the chronic disease in humans most associated with age. Copyright © 2016 Elsevier Ltd. All rights reserved.

Sex differences in discriminative power of volleyball game-related statistics.

Science.gov (United States)

João, Paulo Vicente; Leite, Nuno; Mesquita, Isabel; Sampaio, Jaime

2010-12-01

To identify sex differences in volleyball game-related statistics, the game-related statistics of several World Championships in 2007 (N=132) were analyzed using the software VIS from the International Volleyball Federation. Discriminant analysis was used to identify the game-related statistics which better discriminated performances by sex. Analysis yielded an emphasis on fault serves (SC = -.40), shot spikes (SC = .40), and reception digs (SC = .31). Specific robust numbers represent that considerable variability was evident in the game-related statistics profile, as men's volleyball games were better associated with terminal actions (errors of service), and women's volleyball games were characterized by continuous actions (in defense and attack). These differences may be related to the anthropometric and physiological differences between women and men and their influence on performance profiles.

Measuring individual significant change on the Beck Depression Inventory-II through IRT-based statistics.

NARCIS (Netherlands)

Brouwer, D.; Meijer, R.R.; Zevalkink, D.J.

2013-01-01

Several researchers have emphasized that item response theory (IRT)-based methods should be preferred over classical approaches in measuring change for individual patients. In the present study we discuss and evaluate the use of IRT-based statistics to measure statistical significant individual

Aging-related episodic memory decline: are emotions the key?

Science.gov (United States)

Kinugawa, Kiyoka; Schumm, Sophie; Pollina, Monica; Depre, Marion; Jungbluth, Carolin; Doulazmi, Mohamed; Sebban, Claude; Zlomuzica, Armin; Pietrowsky, Reinhard; Pause, Bettina; Mariani, Jean; Dere, Ekrem

2013-01-01

Episodic memory refers to the recollection of personal experiences that contain information on what has happened and also where and when these events took place. Episodic memory function is extremely sensitive to cerebral aging and neurodegerative diseases. We examined episodic memory performance with a novel test in young (N = 17, age: 21–45), middle-aged (N = 16, age: 48–62) and aged but otherwise healthy participants (N = 8, age: 71–83) along with measurements of trait and state anxiety. As expected we found significantly impaired episodic memory performance in the aged group as compared to the young group. The aged group also showed impaired working memory performance as well as significantly decreased levels of trait anxiety. No significant correlation between the total episodic memory and trait or state anxiety scores was found. The present results show an age-dependent episodic memory decline along with lower trait anxiety in the aged group. Yet, it still remains to be determined whether this difference in anxiety is related to the impaired episodic memory performance in the aged group. PMID:23378831

Mouse models of telomere dysfunction phenocopy skeletal changes found in human age-related osteoporosis

Directory of Open Access Journals (Sweden)

Tracy A. Brennan

2014-05-01

��/−Terc−/− mice had a statistically significant increase in bone-marrow fat content compared with young WT mice, which remained elevated in aged double mutants. Taken together, our results suggest that Terc−/− and Wrn−/−Terc−/− mutants recapitulate the human bone aging phenotype and are useful models for studying age-related osteoporosis.

Teasing apart the relations between age, birth cohort, and vocational interests.

Science.gov (United States)

Leuty, Melanie E; Hansen, Jo-Ida C

2014-04-01

Empirical evidence supports that aging is related to differences in work attitudes and motivation (Inceoglu, Segers, & Bartram, 2012; Kooij, de Lange, Jansen, Kanfer, & Kikkers, 2011; Ng & Feldman, 2008, 2010), but little research has explored the relations between age and vocational interests. Furthermore, recent studies of age and work attitudes suggest that generational experiences (i.e., birth year) may account for age differences in the workplace (Inceoglu et al., 2012; Ng & Feldman, 2008, 2010), which in turn suggests that researchers need to incorporate both age and birth cohort effects in their designs. Thus, this study was designed to explore the relations of age at the time of testing and birth year to vocational interests using a sample of adults (N = 1,792) collected over a period of 3 decades. As expected, age was not a significant predictor of most interests, but birth year also was not found to predict most interests, with the significant prediction of Realistic interests by both age and birth year being the exception. Gender, however, significantly predicted most areas of interests. Neither age nor gender moderated any relationships between birth year and interests. Results suggest that birth year and age were minimally related to interests as all effect sizes were small. Discussion of the results illustrates the need for further research on this issue and also offers considerations for attracting and retaining different generations of workers in light of the findings. (PsycINFO Database Record (c) 2014 APA, all rights reserved).

Sex and age related differences in postmyelographic adverse reactions

International Nuclear Information System (INIS)

Maly, P.

1989-01-01

Differences in frequency of postmyelographic adverse reactions were analyzed with respect to sex and age in a prospective study including 1026 patients injected with metrizamide and 739 injected with iohexol. Regardless of the type of contrast medium or myelography, all types of adverse reactions were 1.4-3.8 times as frequent in women as in men. Most of the differences were statistically significant. Headache was more frequent, while vomiting and dizziness were less frequent in both women and men aged 26-50 years compared with those over 50 years of age. Dizziness and increased low back pain were consistently reported spontaneously by the patients less frequently than emerged via formal interview. The large differences between the sexes suggest that further research on contrast media toxicity would be best performed with separation of the data by gender. (orig.)

Multiple Brain Markers are Linked to Age-Related Variation in Cognition

Science.gov (United States)

Hedden, Trey; Schultz, Aaron P.; Rieckmann, Anna; Mormino, Elizabeth C.; Johnson, Keith A.; Sperling, Reisa A.; Buckner, Randy L.

2016-01-01

Age-related alterations in brain structure and function have been challenging to link to cognition due to potential overlapping influences of multiple neurobiological cascades. We examined multiple brain markers associated with age-related variation in cognition. Clinically normal older humans aged 65–90 from the Harvard Aging Brain Study (N = 186) were characterized on a priori magnetic resonance imaging markers of gray matter thickness and volume, white matter hyperintensities, fractional anisotropy (FA), resting-state functional connectivity, positron emission tomography markers of glucose metabolism and amyloid burden, and cognitive factors of processing speed, executive function, and episodic memory. Partial correlation and mediation analyses estimated age-related variance in cognition shared with individual brain markers and unique to each marker. The largest relationships linked FA and striatum volume to processing speed and executive function, and hippocampal volume to episodic memory. Of the age-related variance in cognition, 70–80% was accounted for by combining all brain markers (but only ∼20% of total variance). Age had significant indirect effects on cognition via brain markers, with significant markers varying across cognitive domains. These results suggest that most age-related variation in cognition is shared among multiple brain markers, but potential specificity between some brain markers and cognitive domains motivates additional study of age-related markers of neural health. PMID:25316342

The Schmidt hammer as a relative-age dating tool and its potential for calibrated-age dating in Holocene glaciated environments

Science.gov (United States)

Shakesby, Richard A.; Matthews, John A.; Owen, Geraint

2006-11-01

The Schmidt hammer is a relatively cheap, portable, sturdy instrument with proven value over the last two decades or so in rapidly dating coarse inorganic deposits of diverse origins. Early views were that its dating role was limited to distinguishing recently exposed from much older. Typically, either a few sites of possibly different ages or occasional older surfaces amongst many young sites were studied. More recently, calibration curves based on individual R-value means from small numbers (2-4) of sites of known ages have been used to estimate the ages of undated sites. We present Schmidt hammer rebound ( R-) values from 28 'Little Ice Age' (and younger), 23 Preboreal and 7 Younger Dryas glaciated surfaces in southern Norway in order, first, to test rigorously the robustness of the instrument as a relative-age dating tool. Despite being obtained from different surfaces (moraines, glaciofluvial deposits and bedrock) and varied metamorphic lithologies, the R-value overall means and 95% confidence intervals for the 'Little Ice Age', Preboreal and Younger Dryas age categories (respectively, 60.0±1.6, 41.6±1.4 and 34.2±2.0) are statistically significantly different. Only two outlying sites in the two younger age categories have overlapping confidence intervals, demonstrating remarkable robustness in differentiating early- and late-Holocene surfaces. The distinction between Preboreal and Younger Dryas sites (with terminal dates factors, including some previously considered critical (instrument wear, operator bias, initial rock surface texture), which emerge either as less important than previously argued or as relatively unimportant, together with others previously unreported (e.g. long-term changes in lichen, soil, snow and vegetation covers). Third, we investigate the potential for calibrated-age dating by applying exploratory, linear rates of R-value decline to selected combinations of sites. The results suggest that error limits of ca ±700 to ±1600 years

Plasma levels of hypoxia-regulated factors in patients with age-related macular degeneration.

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Ioanna, Zygoula; Christian, Schori; Christian, Grimm; Daniel, Barthelmes

2018-02-01

Various hypoxia-related proteins are differentially expressed in the retina and secreted to the vitreous and/or aqueous humor of patients affected by dry or neovascular age-related macular degeneration (nAMD). To determine whether these conditions alter concentrations of cytokines also in the systemic circulation, we measured plasma levels of six hypoxia-related proteins. Plasma was prepared from EDTA blood that was collected from patients affected by dry AMD (n = 5), nAMD (n = 11), proliferative diabetic retinopathy (PDR; n = 9), and patients with an epiretinal membrane (ERM; n = 11). ERM samples served as negative controls, PDR samples as positive controls. Protein concentrations of vascular endothelial growth factor (VEGF), erythropoietin (EPO), angiopoietin-like 4 (ANGPTL4), placental growth factor (PlGF), tumor necrosis factor alpha (TNF-α), and pigment epithelium-derived factor (PEDF) were determined by enzyme-linked immunosorbent assay (ELISA). The concentration of PlGF was significantly increased in plasma of patients affected by nAMD. Although no statistically significant differences were found for EPO, ANGPTL4, PlGF, TNF-α, and PEDF, the mean concentration of VEGF was lowest in the nAMD group. Plasma concentrations of the six factors did not correlate with gender or age of patients. nAMD may increase plasma concentrations of PlGF, making it a candidate as a biomarker for the neovascular form of AMD. Other factors, however, were not differentially regulated, suggesting that their systemic concentrations are not generally increased in hypoxia-related retinal diseases.

Age-related changes in human tendo calcaneus collagen fibrils

International Nuclear Information System (INIS)

Sargon, Mustafa F.; Ozlu, Korhan; Oken, Fuad

2005-01-01

The ruptures of tendo calcaneus often occur between the age group of 30-45 years as described by several text books. It is also described that some diseases and drugs are said to be responsible in the etiology; however, there are no studies related with the detailed histological structure of collagen fibrils found in the tendon in the age groups of humans. In view there of, this study was aimed to obtain further information on the etiology and to find an answer regarding the frequency the ruptures occurring between the age of 30-45 years in human. In the study, the biopsy specimen taken from 28 patients age (1-68) years who had undergone surgery due to tendo calcaneus ruptures or acilloplasty operations were examined by transmission electron microscope. All the specimens were prepared according to routine electronic microscope tissue preparation technique. The patients were divided into 7 age groups (1-9, 10-19, 20-29, 30-39, 40-49, 50-59, >60 years) and there were 4 patients in each group. The transverse diameters of collagen fibers were measured from the ultra thin sections and statistical analysis of the results were performed. The study was carried out in the electron microscopy laboratory of the Anatomy Department of Hacettepe University, Ankara, Turkey between January 2004 and September 2004. The diameters of the collagen fibers were higher in the 20-29 year-old groups compared to other groups and it showed a statistically significant difference. In patients who were in the 30-39 year old group or older, the diameters of the collagen fibers were lesser than the 20-29 year-old group. However, an increase was observed in the collagen fibril concentration of these groups. In examination of the specimens of patients who were under 20-year old, the diameter of the collagen fibers were less than 20-29 year -old group. The electron microscopic appearance of the tissue sample of a one year-old patient had a specific organization and in this patient, both the

Smoking,serum antioxidant vitamin levels and age-related macular degeneration

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Sezen Akkaya Çakir

2014-05-01

Full Text Available AIM: To evaluate associations between the grades of age related macular degeneration(AMDand serum levels of antioxidant vitamins(vitamin A, C and Eand smoking. METHODS: Fifty-three AMD patients and 31 individuals having ages matching with the patient group were enrolled the study. Colored fundus photographs of the macula were used to place participants(n=84into one of the five groups(Grade I-Vbased on the frequency and severity of the lesions associated with AMD. Serum antioxidant vitamin levels were measured using High Performance Liquid Chromatography(HPLC. Smoking status was classified as non-smoker, ex-smoker and current smoker. Total number of packs smoked per year, was defined.RESULTS: The distribution of vitamin A, E, and C levels were 0.874±0.326mg/L, 10.739±4.874mg/L, 1.737±0.447mg/L in control group and 0.880±0.305mg/L, 9.487±6.060mg/L, 1.870±2.191mg/L in AMD group, respectively. The difference between AMD and control group was not statistically significant for vitamin A, E and C levels(P>0.05. There were no significant differences between subgroups of AMD for vitamin A(P=0.881and vitamin E(P=0.293but there was a contradicting rise of vitamin C levels(P=0.044with increasing levels of the disease. There were no significant differences between AMD and control group regarding smoking status, but there was a significant difference for total number of packs smoked per year(P=0.02. An increase of number of total packs smoked per year was determined along with the rising grade of AMD(P=0.007. CONCLUSION: We found no relation between AMD and serum levels of vitamin A and E but vitamin C levels was increase with AMD grades unexpectedly. We found dose-response relationship between smoking and AMD.

Magnetic resonance fiber density mapping of age-related white matter changes

International Nuclear Information System (INIS)

Stadlbauer, Andreas; Ganslandt, Oliver; Salomonowitz, Erich; Buchfelder, Michael; Hammen, Thilo; Bachmair, Johanna; Eberhardt, Knut

2012-01-01

Objectives: To introduce fiber density mapping (FDM) for investigation of age-related white matter (WM) changes and to compare its capabilities with conventional diffusion tensor imaging (DTI) post-processing. Methods: DTI data with 1.9 mm 3 isotropic voxels were acquired from 44 healthy volunteers (18–88 years) at 3 T. FDM is a 3-step approach which includes diagonalization of the diffusion tensor, fiber reconstruction for the whole brain, and calculation of fiber density (FD) values. Maps of fractional anisotropy (FA) and mean diffusivity (MD) were additionally calculated. Voxel-based analyses were performed to determine volume clusters of significant correlation with age. Bivariate linear regression models and Hotelling–Williams tests were used to detect significant differences between correlations. Results: FDM detected a larger WM volume affected by age-related changes concomitant with fewer significant clusters compared to FA and MD. This indicates that WM alterations due to normal aging occur rather globally than locally. FD values showed a significant stronger correlation with age in frontal lobes (prefrontal and precentral gyrus), limbic lobes (cingulate and parahippocampal gyrus), the corpus callosum (genu) and temporal lobes. Conclusions: FDM shows higher sensitivity for detection of age-related WM changes because it includes all surrounding fiber structures into the evaluation of each DTI data voxel.

Magnetic resonance fiber density mapping of age-related white matter changes

Energy Technology Data Exchange (ETDEWEB)

Stadlbauer, Andreas, E-mail: andi@nmr.at [MR Physics Group, Department of Radiology, Landesklinikum St. Poelten, Propst Fuehrer Strasse 4, A-3100 St. Poelten (Austria); Department of Neurosurgery, University of Erlangen-Nuremberg, Schwabachanlage 6, 91054 Erlangen (Germany); Ganslandt, Oliver [Department of Neurosurgery, University of Erlangen-Nuremberg, Schwabachanlage 6, 91054 Erlangen (Germany); Salomonowitz, Erich [MR Physics Group, Department of Radiology, Landesklinikum St. Poelten, Propst Fuehrer Strasse 4, A-3100 St. Poelten (Austria); Buchfelder, Michael [Department of Neurosurgery, University of Erlangen-Nuremberg, Schwabachanlage 6, 91054 Erlangen (Germany); Hammen, Thilo [Department of Neurology, Epilepsy Center, University of Erlangen-Nuremberg, Schwabachanlage 6, D-90429 Erlangen (Germany); Bachmair, Johanna [MR Physics Group, Department of Radiology, Landesklinikum St. Poelten, Propst Fuehrer Strasse 4, A-3100 St. Poelten (Austria); Eberhardt, Knut [Krankenhaus Schloss Werneck, MRT-Kompetenzzentrum, Balthasar-Neumann-Platz 1, D-97440 Werneck (Germany)

2012-12-15

Objectives: To introduce fiber density mapping (FDM) for investigation of age-related white matter (WM) changes and to compare its capabilities with conventional diffusion tensor imaging (DTI) post-processing. Methods: DTI data with 1.9 mm{sup 3} isotropic voxels were acquired from 44 healthy volunteers (18–88 years) at 3 T. FDM is a 3-step approach which includes diagonalization of the diffusion tensor, fiber reconstruction for the whole brain, and calculation of fiber density (FD) values. Maps of fractional anisotropy (FA) and mean diffusivity (MD) were additionally calculated. Voxel-based analyses were performed to determine volume clusters of significant correlation with age. Bivariate linear regression models and Hotelling–Williams tests were used to detect significant differences between correlations. Results: FDM detected a larger WM volume affected by age-related changes concomitant with fewer significant clusters compared to FA and MD. This indicates that WM alterations due to normal aging occur rather globally than locally. FD values showed a significant stronger correlation with age in frontal lobes (prefrontal and precentral gyrus), limbic lobes (cingulate and parahippocampal gyrus), the corpus callosum (genu) and temporal lobes. Conclusions: FDM shows higher sensitivity for detection of age-related WM changes because it includes all surrounding fiber structures into the evaluation of each DTI data voxel.

Experience-based attenuation of age-related differences in music cognition tasks.

Science.gov (United States)

Meinz, E J

2000-06-01

Pianists of a wide experience and age range were tested on measures of musical memory and musical perceptual speed to better understand the effects of experience on age-cognition relations. Experience-related attenuation might be in the form of an Age x Experience interaction or in the form of a "confounding" of age and experience such that positive age-experience relations offset negative age-cognition relations. It was predicted that the former, considered evidence for disuse interpretations of aging, would be likely to emerge in tasks with strong experience effects and strong age-related declines among inexperienced individuals. However, in no case were the interactions of age and experience on the memory or perceptual speed variables significant. There was, however, evidence that high levels of experience in the older participants partially attenuated the negative effects of age on the memory and perceptual speed tasks.

Aging Is Not a Disease: Distinguishing Age-Related Macular Degeneration from Aging

Science.gov (United States)

Ardeljan, Daniel; Chan, Chi-Chao

2013-01-01

Age-related macular degeneration (AMD) is a disease of the outer retina, characterized most significantly by atrophy of photoreceptors and retinal pigment epithelium accompanied with or without choroidal neovascularization. Development of AMD has been recognized as contingent on environmental and genetic risk factors, the strongest being advanced age. In this review, we highlight pathogenic changes that destabilize ocular homeostasis and promote AMD development. With normal aging, photoreceptors are steadily lost, Bruch's membrane thickens, the choroid thins, and hard drusen may form in the periphery. In AMD, many of these changes are exacerbated in addition to the development of disease-specific factors such as soft macular drusen. Para-inflammation, which can be thought of as an intermediate between basal and robust levels of inflammation, develops within the retina in an attempt to maintain ocular homeostasis, reflected by increased expression of the anti-inflammatory cytokine IL-10 coupled with shifts in macrophage plasticity from the pro-inflammatory M1 to the anti-inflammatory M2 polarization. In AMD, imbalances in the M1 and M2 populations together with activation of retinal microglia are observed and potentially contribute to tissue degeneration. Nonetheless, the retina persists in a state of chronic inflammation and increased expression of certain cytokines and inflammasomes is observed. Since not everyone develops AMD, the vital question to ask is how the body establishes a balance between normal age-related changes and the pathological phenotypes in AMD. PMID:23933169

Transient Relative Age Effects across annual age groups in National level Australian Swimming.

Science.gov (United States)

Cobley, Stephen; Abbott, Shaun; Dogramaci, Sera; Kable, Adam; Salter, James; Hintermann, Mirjam; Romann, Michael

2017-12-29

To determine the prevalence, magnitude and transient patterning of Relative Age Effects (RAEs) according to sex and stroke event across all age-groups at the Australian National age swimming Championships. Repeated years of cross-sectional participation data were examined. Participants were 6014 unique male (3185) and female (2829) swimmers (aged 12-18 years) who participated in Freestyle (50, 400m) and/or Breaststroke (100, 200m) at the National age swimming Championships between 2000-2014 (inclusive). RAE prevalence, magnitude and transience were determined using Chi-square tests and Cramer's V estimates for effect size. Odds Ratios (OR) and 95% Confidence Intervals (CI) examined relative age quartile discrepancies. These steps were applied across age-groups and according to sex and each stroke event. Consistent RAEs with large-medium effect sizes were evident for males at 12-15 years of age respectively, and with large-medium effects for females at 12-14 respectively across all four swimming strokes. RAE magnitude then consistently reduced with age across strokes (e.g., Q1 vs. Q4 OR range 16year old males=0.94-1.20; females=0.68-1.41). With few exceptions, by 15-16 years RAEs had typically dissipated; and by 17-18 years, descriptive and significant inverse RAEs emerged, reflecting overrepresentation of relatively younger swimmers. Performance advantages associated with relative age (and thereby likely growth and maturation) are transient. Greater consideration of transient performance and participation in athlete development systems is necessary. This may include revising the emphasis of sport programmes according to developmental stages and delaying forms of athlete selection to improve validity. Copyright © 2018 Sports Medicine Australia. Published by Elsevier Ltd. All rights reserved.

[Factors Related to Presenteeism in Young and Middle-aged Nurses].

Science.gov (United States)

Yoshida, Mami; Miki, Akiko

2018-04-03

Presenteeism is considered to be not only a work-related stressor but also a factor involved in the development of workaholism and error proneness, which is often described as careless. Additionally, increasing health issues arising from aging suggest the possibility that presenteeism in middle-aged nurses is different than that in young ones. Therefore, the present study aimed to identify and tease apart factors involved in presenteeism among young and middle-aged nurses. An anonymous self-administered questionnaire survey was conducted among 2,006 nurses working at 10 hospitals. In total, 761 nurses aged nurses aged ≥40 years were enrolled in this study. Work Impairment Scores (WIS) on the Japanese version of the Stanford Presenteeism Scale were measured for presenteeism. Job stressors, workaholism, and error proneness were measured for related factors. Multiple regression analysis was conducted after determining the WIS as the dependent variable and related factors as independent variables. Overall, 70.8% of the young nurses reported health problems compared to 82.5% of the middle-aged nurses. However, WIS in young nurses was significantly higher than that in middle-aged ones (p nurses showed a significant relationship with the degree of stressors, "difficulty of work" (β = 0.28, p nurses showed a significant relationship with "cognitive narrowing" (β = 0.29, p nurses does not necessarily lower their working capacity. Also, compared to young nurses, the degree of failing tendency, rather than the degree of job stressors, was more related to presenteeism for middle-aged nurses. It can be considered that middle-aged nurses simply realize that their working ability is hindered because of incidents resulting from attention narrowing. As fatigue and state of tension tend to cause narrowing of attention, it may be necessary to reduce such risks and adjust work environments so mistakes can be avoided.

Risk factors of age-related macular degeneration in Argentina

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María Eugenia Nano

2013-04-01

Full Text Available PURPOSES: To assess the risk factors of age-related macular degeneration in Argentina using a case-control study. METHODS: Surveys were used for subjects' antioxidant intake, age/gender, race, body mass index, hypertension, diabetes (and type of treatment, smoking, sunlight exposure, red meat consumption, fish consumption, presence of age-related macular degeneration and family history of age-related macular degeneration. Main effects models for logistic regression and ordinal logistic regression were used to analyze the results. RESULTS: There were 175 cases and 175 controls with a mean age of 75.4 years and 75.5 years, respectively, of whom 236 (67.4% were female. Of the cases with age-related macular degeneration, 159 (45.4% had age-related macular degeneration in their left eyes, 154 (44.0% in their right eyes, and 138 (39.4% in both eyes. Of the cases with age-related macular degeneration in their left eyes, 47.8% had the dry type, 40.3% had the wet type, and the type was unknown for 11.9%. The comparable figures for right eyes were: 51.9%, 34.4%, and 13.7%, respectively. The main effects model was dominated by higher sunlight exposure (OR [odds ratio]: 3.3 and a family history of age-related macular degeneration (OR: 4.3. Other factors included hypertension (OR: 2.1, smoking (OR: 2.2, and being of the Mestizo race, which lowered the risk of age-related macular degeneration (OR: 0.40. Red meat/fish consumption, body mass index, and iris color did not have an effect. Higher age was associated with progression to more severe age-related macular degeneration. CONCLUSION: Sunlight exposure, family history of age-related macular degeneration, and an older age were the significant risk factors. There may be other variables, as the risk was not explained very well by the existing factors. A larger sample may produce different and better results.

Insufficient DNA methylation affects healthy aging and promotes age-related health problems.

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Liu, Liang; van Groen, Thomas; Kadish, Inga; Li, Yuanyuan; Wang, Deli; James, Smitha R; Karpf, Adam R; Tollefsbol, Trygve O

2011-08-01

DNA methylation plays an integral role in development and aging through epigenetic regulation of genome function. DNA methyltransferase 1 (Dnmt1) is the most prevalent DNA methyltransferase that maintains genomic methylation stability. To further elucidate the function of Dnmt1 in aging and age-related diseases, we exploited the Dnmt1+/- mouse model to investigate how Dnmt1 haploinsufficiency impacts the aging process by assessing the changes of several major aging phenotypes. We confirmed that Dnmt1 haploinsufficiency indeed decreases DNA methylation as a result of reduced Dnmt1 expression. To assess the effect of Dnmt1 haploinsufficiency on general body composition, we performed dual-energy X-ray absorptiometry analysis and showed that reduced Dnmt1 activity decreased bone mineral density and body weight, but with no significant impact on mortality or body fat content. Using behavioral tests, we demonstrated that Dnmt1 haploinsufficiency impairs learning and memory functions in an age-dependent manner. Taken together, our findings point to the interesting likelihood that reduced genomic methylation activity adversely affects the healthy aging process without altering survival and mortality. Our studies demonstrated that cognitive functions of the central nervous system are modulated by Dnmt1 activity and genomic methylation, highlighting the significance of the original epigenetic hypothesis underlying memory coding and function.

The adipokine leptin increases skeletal muscle mass and significantly alters skeletal muscle miRNA expression profile in aged mice

International Nuclear Information System (INIS)

Hamrick, Mark W.; Herberg, Samuel; Arounleut, Phonepasong; He, Hong-Zhi; Shiver, Austin; Qi, Rui-Qun; Zhou, Li; Isales, Carlos M.

2010-01-01

Research highlights: → Aging is associated with muscle atrophy and loss of muscle mass, known as the sarcopenia of aging. → We demonstrate that age-related muscle atrophy is associated with marked changes in miRNA expression in muscle. → Treating aged mice with the adipokine leptin significantly increased muscle mass and the expression of miRNAs involved in muscle repair. → Recombinant leptin therapy may therefore be a novel approach for treating age-related muscle atrophy. -- Abstract: Age-associated loss of muscle mass, or sarcopenia, contributes directly to frailty and an increased risk of falls and fractures among the elderly. Aged mice and elderly adults both show decreased muscle mass as well as relatively low levels of the fat-derived hormone leptin. Here we demonstrate that loss of muscle mass and myofiber size with aging in mice is associated with significant changes in the expression of specific miRNAs. Aging altered the expression of 57 miRNAs in mouse skeletal muscle, and many of these miRNAs are now reported to be associated specifically with age-related muscle atrophy. These include miR-221, previously identified in studies of myogenesis and muscle development as playing a role in the proliferation and terminal differentiation of myogenic precursors. We also treated aged mice with recombinant leptin, to determine whether leptin therapy could improve muscle mass and alter the miRNA expression profile of aging skeletal muscle. Leptin treatment significantly increased hindlimb muscle mass and extensor digitorum longus fiber size in aged mice. Furthermore, the expression of 37 miRNAs was altered in muscles of leptin-treated mice. In particular, leptin treatment increased the expression of miR-31 and miR-223, miRNAs known to be elevated during muscle regeneration and repair. These findings suggest that aging in skeletal muscle is associated with marked changes in the expression of specific miRNAs, and that nutrient-related hormones such as leptin

The adipokine leptin increases skeletal muscle mass and significantly alters skeletal muscle miRNA expression profile in aged mice

Energy Technology Data Exchange (ETDEWEB)

Hamrick, Mark W., E-mail: mhamrick@mail.mcg.edu [Department of Cellular Biology and Anatomy, Institute of Molecular Medicine and Genetics, Medical College of Georgia, Augusta, GA (United States); Department of Orthopaedic Surgery, Institute of Molecular Medicine and Genetics, Medical College of Georgia, Augusta, GA (United States); Herberg, Samuel; Arounleut, Phonepasong [Department of Cellular Biology and Anatomy, Institute of Molecular Medicine and Genetics, Medical College of Georgia, Augusta, GA (United States); Department of Orthopaedic Surgery, Institute of Molecular Medicine and Genetics, Medical College of Georgia, Augusta, GA (United States); He, Hong-Zhi [Henry Ford Immunology Program, Henry Ford Health System, Detroit, MI (United States); Department of Dermatology, Henry Ford Health System, Detroit, MI (United States); Shiver, Austin [Department of Cellular Biology and Anatomy, Institute of Molecular Medicine and Genetics, Medical College of Georgia, Augusta, GA (United States); Department of Orthopaedic Surgery, Institute of Molecular Medicine and Genetics, Medical College of Georgia, Augusta, GA (United States); Qi, Rui-Qun [Henry Ford Immunology Program, Henry Ford Health System, Detroit, MI (United States); Department of Dermatology, Henry Ford Health System, Detroit, MI (United States); Zhou, Li [Henry Ford Immunology Program, Henry Ford Health System, Detroit, MI (United States); Department of Dermatology, Henry Ford Health System, Detroit, MI (United States); Department of Internal Medicine, Henry Ford Health System, Detroit, MI (United States); Isales, Carlos M. [Department of Cellular Biology and Anatomy, Institute of Molecular Medicine and Genetics, Medical College of Georgia, Augusta, GA (United States); Department of Orthopaedic Surgery, Institute of Molecular Medicine and Genetics, Medical College of Georgia, Augusta, GA (United States); others, and

2010-09-24

Research highlights: {yields} Aging is associated with muscle atrophy and loss of muscle mass, known as the sarcopenia of aging. {yields} We demonstrate that age-related muscle atrophy is associated with marked changes in miRNA expression in muscle. {yields} Treating aged mice with the adipokine leptin significantly increased muscle mass and the expression of miRNAs involved in muscle repair. {yields} Recombinant leptin therapy may therefore be a novel approach for treating age-related muscle atrophy. -- Abstract: Age-associated loss of muscle mass, or sarcopenia, contributes directly to frailty and an increased risk of falls and fractures among the elderly. Aged mice and elderly adults both show decreased muscle mass as well as relatively low levels of the fat-derived hormone leptin. Here we demonstrate that loss of muscle mass and myofiber size with aging in mice is associated with significant changes in the expression of specific miRNAs. Aging altered the expression of 57 miRNAs in mouse skeletal muscle, and many of these miRNAs are now reported to be associated specifically with age-related muscle atrophy. These include miR-221, previously identified in studies of myogenesis and muscle development as playing a role in the proliferation and terminal differentiation of myogenic precursors. We also treated aged mice with recombinant leptin, to determine whether leptin therapy could improve muscle mass and alter the miRNA expression profile of aging skeletal muscle. Leptin treatment significantly increased hindlimb muscle mass and extensor digitorum longus fiber size in aged mice. Furthermore, the expression of 37 miRNAs was altered in muscles of leptin-treated mice. In particular, leptin treatment increased the expression of miR-31 and miR-223, miRNAs known to be elevated during muscle regeneration and repair. These findings suggest that aging in skeletal muscle is associated with marked changes in the expression of specific miRNAs, and that nutrient-related

Thresholds for statistical and clinical significance in systematic reviews with meta-analytic methods

DEFF Research Database (Denmark)

Jakobsen, Janus Christian; Wetterslev, Jorn; Winkel, Per

2014-01-01

BACKGROUND: Thresholds for statistical significance when assessing meta-analysis results are being insufficiently demonstrated by traditional 95% confidence intervals and P-values. Assessment of intervention effects in systematic reviews with meta-analysis deserves greater rigour. METHODS......: Methodologies for assessing statistical and clinical significance of intervention effects in systematic reviews were considered. Balancing simplicity and comprehensiveness, an operational procedure was developed, based mainly on The Cochrane Collaboration methodology and the Grading of Recommendations...... Assessment, Development, and Evaluation (GRADE) guidelines. RESULTS: We propose an eight-step procedure for better validation of meta-analytic results in systematic reviews (1) Obtain the 95% confidence intervals and the P-values from both fixed-effect and random-effects meta-analyses and report the most...

Age-Related Gene Expression Differences in Monocytes from Human Neonates, Young Adults, and Older Adults.

Science.gov (United States)

Lissner, Michelle M; Thomas, Brandon J; Wee, Kathleen; Tong, Ann-Jay; Kollmann, Tobias R; Smale, Stephen T

2015-01-01

A variety of age-related differences in the innate and adaptive immune systems have been proposed to contribute to the increased susceptibility to infection of human neonates and older adults. The emergence of RNA sequencing (RNA-seq) provides an opportunity to obtain an unbiased, comprehensive, and quantitative view of gene expression differences in defined cell types from different age groups. An examination of ex vivo human monocyte responses to lipopolysaccharide stimulation or Listeria monocytogenes infection by RNA-seq revealed extensive similarities between neonates, young adults, and older adults, with an unexpectedly small number of genes exhibiting statistically significant age-dependent differences. By examining the differentially induced genes in the context of transcription factor binding motifs and RNA-seq data sets from mutant mouse strains, a previously described deficiency in interferon response factor-3 activity could be implicated in most of the differences between newborns and young adults. Contrary to these observations, older adults exhibited elevated expression of inflammatory genes at baseline, yet the responses following stimulation correlated more closely with those observed in younger adults. Notably, major differences in the expression of constitutively expressed genes were not observed, suggesting that the age-related differences are driven by environmental influences rather than cell-autonomous differences in monocyte development.

Age-related changes in thoracic skeletal geometry of elderly females.

Science.gov (United States)

Holcombe, Sven A; Wang, Stewart C; Grotberg, James B

2017-05-29

Both females and the elderly have been identified as vulnerable populations with increased injury and mortality risk in multiple crash scenarios. Particularly in frontal impacts, older females show higher risk to the chest and thorax than their younger or male counterparts. Thoracic geometry plays a role in this increase, and this study aims to quantify key parts of that geometry in a way that can directly inform human body models that incorporate the concept of person age. Computed tomography scans from 2 female subject groups aged 20-35 and 65-99 were selected from the International Center for Automotive Medicine scan database representing young and old female populations. A model of thoracic skeletal anatomy was built for each subject from independent parametric models of the spine, ribs, and sternum, along with further parametric models of those components' spatial relationships. Parameter values between the 2 groups are directly compared, and average parameter values within each group are used to generate statistically average skeletal geometry for young and old females. In addition to the anatomic measures explicitly used in the parameterization scheme, key measures of rib cage depth and spine curvature are taken from both the underlying subject pool and from the resultant representative geometries. Statistically significant differences were seen between the young and old groups' spine and rib anatomic components, with no significant differences in local sternal geometry found. Vertebral segments in older females had higher angles relative to their inferior neighbors, providing a quantification of the kyphotic curvature known to be associated with age. Ribs in older females had greater end-to-end span, greater aspect ratio, and reduced out-of-plane deviation, producing an elongated and overall flatter curvature that leads to distal rib ends extending further anteriorly in older individuals. Combined differences in spine curvature and rib geometry led to an 18

Age-related changes assessed by peripheral QCT in healthy Italian women

International Nuclear Information System (INIS)

Guglielmi, G.; Serio, A. de; Cammisa, M.; Fusilli, S.; Scillitani, A.; Chiodini, I.; Torlontano, M.

2000-01-01

The purpose of this study was to describe the normal cross-sectional pattern of radial bone loss associated with aging in healthy women and to generate a normative database using peripheral quantitative computed tomography (pQCT). Subjects with suspected conditions affecting bone metabolism or receiving any drugs affecting bone mineralization were excluded. The trabecular bone mineral density (BMD) and the total bone density of the ultradistal radius at the nondominant forearm was measured using the Norland-Stratec XCT-960 pQCT scanner in 386 healthy pre-, peri-, and postmenopausal females aged 15-81 years. The long-term in vivo precision error was 1.6% CV (coefficient of variation) for trabecular and 0.8% CV for total BMD measurements. The highest value of trabecular and total BMD measured was observed at the age group 15-39 years. Beyond these ages both trabecular and total BMD showed a linear decline with aging, decreasing by an overall slope of -1.28 and -0.55 mg/cm 3 per year for total and trabecular BMD measurements, respectively. The test of parallelism between the regression slopes of the peri- and postmenopausal women showed a statistically significant difference for total BMD measurement (p=0.003). Measurement of total and trabecular BMD was not influenced by weight, height or body mass index, but it was correlated with natural logarithm of years since menopause. We conclude that pQCT of the ultradistal radius is a precise method for measuring the true volumetric BMD and for detecting age-related bone loss in the trabecular and total bone of female subjects encompassing the adult age range and menopausal status. (orig.)

Age-related changes assessed by peripheral QCT in healthy Italian women

Energy Technology Data Exchange (ETDEWEB)

Guglielmi, G.; Serio, A. de; Cammisa, M. [Scientific Institute Hospital ' ' Casa Sollievo della Sofferenza' ' , San Giovanni Rotondo (Italy). Dept. of Radiology; Fusilli, S. [Scientific Institute Hospital ' ' Casa Sollievo della Sofferenza' ' , San Giovanni Rotondo (Italy). Dept. of Clinical Pathology; Scillitani, A.; Chiodini, I.; Torlontano, M. [Scientific Institute Hospital ' ' Casa Sollievo della Sofferenza' ' , San Giovanni Rotondo (Italy). Division of Endocrinology

2000-04-01

The purpose of this study was to describe the normal cross-sectional pattern of radial bone loss associated with aging in healthy women and to generate a normative database using peripheral quantitative computed tomography (pQCT). Subjects with suspected conditions affecting bone metabolism or receiving any drugs affecting bone mineralization were excluded. The trabecular bone mineral density (BMD) and the total bone density of the ultradistal radius at the nondominant forearm was measured using the Norland-Stratec XCT-960 pQCT scanner in 386 healthy pre-, peri-, and postmenopausal females aged 15-81 years. The long-term in vivo precision error was 1.6% CV (coefficient of variation) for trabecular and 0.8% CV for total BMD measurements. The highest value of trabecular and total BMD measured was observed at the age group 15-39 years. Beyond these ages both trabecular and total BMD showed a linear decline with aging, decreasing by an overall slope of -1.28 and -0.55 mg/cm{sup 3} per year for total and trabecular BMD measurements, respectively. The test of parallelism between the regression slopes of the peri- and postmenopausal women showed a statistically significant difference for total BMD measurement (p=0.003). Measurement of total and trabecular BMD was not influenced by weight, height or body mass index, but it was correlated with natural logarithm of years since menopause. We conclude that pQCT of the ultradistal radius is a precise method for measuring the true volumetric BMD and for detecting age-related bone loss in the trabecular and total bone of female subjects encompassing the adult age range and menopausal status. (orig.)

Demographic features and premorbid personality disorder traits in relation to age of onset and sex in paranoid schizophrenia.

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Skokou, Maria; Gourzis, Philippos

2014-03-30

Personality disorders in the premorbid period of schizophrenia and particularly in relation to age of onset and sex, seem to be a rather under-researched area. In the present study, 88 patients with paranoid schizophrenia were examined, regarding demographic characteristics and premorbid personality disorder traits, in order to investigate for differences in the premorbid period of the disease, in relation to age of onset and sex. Age cutoff points were set at personality disorder traits were retrospectively assessed by using the Structured Clinical Interview for DSM-IV-Patient Edition for Axis II disorders (SCID-II). Comparisons were performed by applying the two-tailed Wilcoxon rank-sum and the χ(2) statistical tests. Young onset patients were characterized by significantly higher proportion of urban birth, single status, more avoidant premorbid personality disorder traits, and less passive-aggressive premorbid personality disorder traits, than late onset counterparts. Differences were more prominently shown in men. Earlier age of onset seems to be associated to increased social inhibition and worse psychosocial adaptation in the premorbid period of paranoid schizophrenia. Copyright © 2014 Elsevier Ireland Ltd. All rights reserved.

Emotion identification and aging: Behavioral and neural age-related changes.

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Gonçalves, Ana R; Fernandes, Carina; Pasion, Rita; Ferreira-Santos, Fernando; Barbosa, Fernando; Marques-Teixeira, João

2018-05-01

Aging is known to alter the processing of facial expressions of emotion (FEE), however the impact of this alteration is less clear. Additionally, there is little information about the temporal dynamics of the neural processing of facial affect. We examined behavioral and neural age-related changes in the identification of FEE using event-related potentials. Furthermore, we analyze the relationship between behavioral/neural responses and neuropsychological functioning. To this purpose, 30 younger adults, 29 middle-aged adults and 26 older adults identified FEE. The behavioral results showed a similar performance between groups. The neural results showed no significant differences between groups for the P100 component and an increased N170 amplitude in the older group. Furthermore, a pattern of asymmetric activation was evident in the N170 component. Results also suggest deficits in facial feature decoding abilities, reflected by a reduced N250 amplitude in older adults. Neuropsychological functioning predicts P100 modulation, but does not seem to influence emotion identification ability. The findings suggest the existence of a compensatory function that would explain the age-equivalent performance in emotion identification. The study may help future research addressing behavioral and neural processes involved on processing of FEE in neurodegenerative conditions. Copyright © 2018 International Federation of Clinical Neurophysiology. Published by Elsevier B.V. All rights reserved.

Neuronal Function in Male Sprague Dawley Rats During Normal Ageing.

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Idowu, A J; Olatunji-Bello, I I; Olagunju, J A

2017-03-06

During normal ageing, there are physiological changes especially in high energy demanding tissues including the brain and skeletal muscles. Ageing may disrupt homeostasis and allow tissue vulnerability to disease. To establish an appropriate animal model which is readily available and will be useful to test therapeutic strategies during normal ageing, we applied behavioral approaches to study age-related changes in memory and motor function as a basis for neuronal function in ageing in male Sprague Dawley rats. 3 months, n=5; 6 months, n=5 and 18 months, n=5 male Sprague Dawley Rats were tested using the Novel Object Recognition Task (NORT) and the Elevated plus Maze (EPM) Test. Data was analyzed by ANOVA and the Newman-Keuls post hoc test. The results showed an age-related gradual decline in exploratory behavior and locomotor activity with increasing age in 3 months, 6 months and 18 months old rats, although the values were not statistically significant, but grooming activity significantly increased with increasing age. Importantly, we established a novel finding that the minimum distance from the novel object was statistically significant between 3 months and 18 months old rats and this may be an index for age-related memory impairment in the NORT. Altogether, we conclude that the male Sprague Dawley rat show age-related changes in neuronal function and may be a useful model for carrying out investigations into the mechanisms involved in normal ageing.

Localization of age-related macular degeneration-associated ARMS2 in cytosol, not mitochondria

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Wang, Gaofeng; Spencer, Kylee L.; Court, Brenda L.; Olson, Lana M.; Scott, William K.; Haines, Jonathan L.; Pericak-Vance, Margaret A.

2010-01-01

PURPOSE To analyze the relationship between ARMS2 and HTRA1 in the association with age-related macular degeneration (AMD) in an independent case-control dataset, and to investigate the subcellular localization of the ARMS2 protein in an in vitro system. METHOD Two SNPs in ARMS2 and HTRA1 were genotyped in 685 cases and 269 controls by Taqman Assay. Allelic association was tested by a χ2 test. A likelihood ratio test (LRT) of full vs. reduced models was utilized to analyze the interaction between ARMS2 and smoking and HTRA1 and smoking, after adjusting for CFH and age. Immunofluorescence and immunoblot were applied to localize ARMS2 in retinal epithelial ARPE-19 cells and COS7 cell transfected by ARMS2 constructs. RESULT Both significantly associated SNP rs10490924 and rs11200638 (P<0.0001) are in strong linkage disequilibrium (LD) (D′=0.97, r2=0.93) that generates virtually identical association test and odds ratios. In separate logistic regression models the interaction effect for both smoking with ARMS2 and with HTRA1 was not statistically significant. Immunofluorescence and immunoblot show that both endogenous and exogenous ARMS2 are mainly distributed in the cytosol, not the mitochondria. Comparing to wild type, ARMS2 A69S is more likely to be associated with cytoskeleton in COS7 cells. CONCLUSIONS The significant associations in ARMS2 and HTRA1 are with polymorphisms in strong LD that confer virtually identical risks, preventing differentiation at the statistical level. We found that ARMS2 was mainly distributed in the cytosol, not in mitochondrial outer membrane as previously reported, suggesting that ARMS2 may not confer risk to AMD through the mitochondrial pathway. PMID:19255159

Reprint of: Aspirin use and early age-related macular degeneration: a meta-analysis.

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Kahawita, Shyalle K; Casson, Robert J

2015-06-01

The aim of this review was to evaluate the evidence for an association between Aspirin use and early age-related macular degeneration (ARMD). A literature search was performed in 5 databases with no restrictions on language or date of publication. Four studies involving 10292 individuals examining the association between aspirin and ARMD met the inclusion criteria. Meta-analysis was carried out by Cochrane Collaboration Review Manager 5.2 software (Cochrane Collaboration, Copenhagen, Denmark). The pooled odd ratios showed that Aspirin use was associated with early ARMD (pooled odds ratio 1.43, 95% CI 1.09-1.88). There is a small but statistically significant association between Aspirin use and early ARMD, which may warrant further investigation. Copyright © 2015. Published by Elsevier Inc.

Radiation therapy for small choroidal neovascularization in age-related macular degeneration

International Nuclear Information System (INIS)

Matsuhashi, Hideaki; Noda, Yasuko; Takahashi, Daisuke; Mariya, Yasushi

2000-01-01

The purpose of this study was to evaluate the effects of radiation therapy on age-related macular degeneration with subfoveal or juxtafoveal choroidal neovascularization ≤1 disc area. Fourteen patients (14 eyes) received a total radiation dose of 10-20 Gy in 5-10 fractions. The mean follow-up time was 22 months. Ten patients (10 eyes) in a control group were followed up for an average of 16 months without treatment. At a 12-month posttreatment examination, funduscopic and angiographic findings showed improvement in 7 eyes (50%), no change in 1 eye (7%), and deterioration in 6 eyes (43%) among the treated patients. The same findings demonstrated improvement in 1 eye (10%), no change in 2 eyes (20%), and deterioration in 7 eyes (70%) among the control patients. This difference was determined to be statistically significant between the two groups by the Mann-Whitney U-test. Visual acuity had improved in 4 eyes (29%), was unchanged in 6 eyes (43%), and had declined in 4 eyes (29%), among the treated patients. Among the control patients, visual acuity had improved in none of the eyes (0%), was unchanged in 6 eyes (60%), and had declined in 4 eyes (40%). The difference in visual acuity between the two groups was not statistically significant. Radiation therapy inhibited small choroidal neovascularization, as seen by funduscopy and angiography, but its effectiveness in improving visual prognosis was not always evident. (author)

Radiation therapy for small choroidal neovascularization in age-related macular degeneration

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Matsuhashi, Hideaki; Noda, Yasuko; Takahashi, Daisuke; Mariya, Yasushi [Hirosaki Univ., Aomori (Japan). School of Medicine

2000-12-01

The purpose of this study was to evaluate the effects of radiation therapy on age-related macular degeneration with subfoveal or juxtafoveal choroidal neovascularization {<=}1 disc area. Fourteen patients (14 eyes) received a total radiation dose of 10-20 Gy in 5-10 fractions. The mean follow-up time was 22 months. Ten patients (10 eyes) in a control group were followed up for an average of 16 months without treatment. At a 12-month posttreatment examination, funduscopic and angiographic findings showed improvement in 7 eyes (50%), no change in 1 eye (7%), and deterioration in 6 eyes (43%) among the treated patients. The same findings demonstrated improvement in 1 eye (10%), no change in 2 eyes (20%), and deterioration in 7 eyes (70%) among the control patients. This difference was determined to be statistically significant between the two groups by the Mann-Whitney U-test. Visual acuity had improved in 4 eyes (29%), was unchanged in 6 eyes (43%), and had declined in 4 eyes (29%), among the treated patients. Among the control patients, visual acuity had improved in none of the eyes (0%), was unchanged in 6 eyes (60%), and had declined in 4 eyes (40%). The difference in visual acuity between the two groups was not statistically significant. Radiation therapy inhibited small choroidal neovascularization, as seen by funduscopy and angiography, but its effectiveness in improving visual prognosis was not always evident. (author)

Ex Vivo Confocal Spectroscopy of Autofluorescence in Age-Related Macular Degeneration.

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Joel Kaluzny

Full Text Available We investigated the autofluorescence (AF signature of the microscopic features of retina with age-related macular degeneration (AMD using 488 nm excitation.The globes of four donors with AMD and four age-matched controls were embedded in paraffin and sectioned through the macula. Sections were excited using a 488 nm argon laser, and the AF emission was captured using a laser scanning confocal microscope (496-610 nm, 6 nm resolution. The data cubes were then analyzed to compare peak emission spectra between the AMD and the controls. Microscopic features, including individual lipofuscin and melanolipofuscin granules, Bruch's Membrane, as well macroscopic features, were considered.Overall, the AMD eyes showed a trend of blue-shifted emission peaks compared with the controls. These differences were statistically significant when considering the emission of the combined RPE/Bruch's Membrane across all the tissue cross-sections (p = 0.02.The AF signatures of ex vivo AMD RPE/BrM show blue-shifted emission spectra (488 nm excitation compared with the control tissue. The magnitude of these differences is small (~4 nm and highlights the potential challenges of detecting these subtle spectral differences in vivo.

CREB Overexpression Ameliorates Age-related Behavioral and Biophysical Deficits

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Yu, Xiao-Wen

Age-related cognitive deficits are observed in both humans and animals. Yet, the molecular mechanisms underlying these deficits are not yet fully elucidated. In aged animals, a decrease in intrinsic excitability of pyramidal neurons from the CA1 sub-region of hippocampus is believed to contribute to age-related cognitive impairments, but the molecular mechanism(s) that modulate both these factors has yet to be identified. Increasing activity of the transcription factor cAMP response element-binding protein (CREB) in young adult rodents has been shown to facilitate cognition, and increase intrinsic excitability of their neurons. However, how CREB changes with age, and how that impacts cognition in aged animals, is not clear. Therefore, we first systematically characterized age- and training-related changes in CREB levels in dorsal hippocampus. At a remote time point after undergoing behavioral training, levels of total CREB and activated CREB (phosphorylated at S133, pCREB) were measured in both young and aged rats. We found that pCREB, but not total CREB was significantly reduced in dorsal CA1 of aged rats. Importantly, levels of pCREB were found to be positively correlated with short-term spatial memory in both young and aged rats i.e. higher pCREB in dorsal CA1 was associated with better spatial memory. These findings indicate that an age-related deficit in CREB activity may contribute to the development of age-related cognitive deficits. However, it was still unclear if increasing CREB activity would be sufficient to ameliorate age-related cognitive, and biophysical deficits. To address this question, we virally overexpressed CREB in CA1, where we found the age-related deficit. Young and aged rats received control or CREB virus, and underwent water maze training. While control aged animals exhibited deficits in long-term spatial memory, aged animals with CREB overexpression performed at levels comparable to young animals. Concurrently, aged neurons

Age-related normal ranges for the Haller index in children

International Nuclear Information System (INIS)

Daunt, Stephen W.; Cohen, Justine H.; Miller, Stephen F.

2004-01-01

The Haller index is an accepted CT method for evaluating thoracic dimensions in patients with pectus excavatum. The purpose of this study is to establish age- and gender-related norms for the Haller index in childhood. We retrospectively reviewed 574 consecutive chest CT examinations (M=285, F=289) performed at our institution from August 2001 through March 2002. Seventeen patients with a history of chest-wall deformity, trauma, or syndrome were excluded, for a total sample size of 557 patients. The Haller index was calculated for each patient, using electronic calipers. The sample population was then separated by gender and placed into 2-year age groupings. Two-way analysis of variance and Tukey's multiple comparisons were performed to determine significance at a=0.05. The least-square mean Haller index values for each age group and gender were calculated with 95% confidence intervals. In both males and females, the 0- to 2-year age group showed a significantly smaller mean Haller index than older children. In addition, females had significantly greater Haller index values than males in the 0- to 6- and 12- to 18-year age groups. The Haller index, a quantitative measurement of chest-wall configuration, demonstrates significant age- and gender-related variability. This should be considered when evaluating the patient with suspected chest-wall deformity. (orig.)

Doubly Disadvantaged? The Relative Age Effect in Poland's Basketball Players.

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Rubajczyk, Krystian; Świerzko, Kamil; Rokita, Andrzej

2017-06-01

The aim of this study was to identify the relative age effect (RAE) in young Polish male (n = 3849) and female (n = 3419) basketball players aged 14 to 22 years competing in the elite games of the Polish Youth Championships. The distribution of birth dates, body height, players' match statistics, and the results of teams participating in championships were identified. The RAE was observed in male and female group, regardless of players age. Nevertheless, the greatest disproportion in the distribution of dates of birth was found in U16 group of boys (V = 0.25, p born in the first half of a calendar year. The research results show the impact of the RAE on the success of youth basketball teams in Poland. The month of birth, body height and sex may determine sporting achievements in youth basketball. Coaches should consider the chronological age and pubertal growth acceleration (APHV-age at peak height velocity) of players to optimize the process of identifying gifted basketball players, especially among boys of 14 years of age.

A data mining approach for classifying DNA repair genes into ageing-related or non-ageing-related

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Vasieva Olga

2011-01-01

Full Text Available Abstract Background The ageing of the worldwide population means there is a growing need for research on the biology of ageing. DNA damage is likely a key contributor to the ageing process and elucidating the role of different DNA repair systems in ageing is of great interest. In this paper we propose a data mining approach, based on classification methods (decision trees and Naive Bayes, for analysing data about human DNA repair genes. The goal is to build classification models that allow us to discriminate between ageing-related and non-ageing-related DNA repair genes, in order to better understand their different properties. Results The main patterns discovered by the classification methods are as follows: (a the number of protein-protein interactions was a predictor of DNA repair proteins being ageing-related; (b the use of predictor attributes based on protein-protein interactions considerably increased predictive accuracy of attributes based on Gene Ontology (GO annotations; (c GO terms related to "response to stimulus" seem reasonably good predictors of ageing-relatedness for DNA repair genes; (d interaction with the XRCC5 (Ku80 protein is a strong predictor of ageing-relatedness for DNA repair genes; and (e DNA repair genes with a high expression in T lymphocytes are more likely to be ageing-related. Conclusions The above patterns are broadly integrated in an analysis discussing relations between Ku, the non-homologous end joining DNA repair pathway, ageing and lymphocyte development. These patterns and their analysis support non-homologous end joining double strand break repair as central to the ageing-relatedness of DNA repair genes. Our work also showcases the use of protein interaction partners to improve accuracy in data mining methods and our approach could be applied to other ageing-related pathways.

Microarray evaluation of age-related changes in human dental pulp.

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Tranasi, Michelangelo; Sberna, Maria Teresa; Zizzari, Vincenzo; D'Apolito, Giuseppe; Mastrangelo, Filiberto; Salini, Luisa; Stuppia, Liborio; Tetè, Stefano

2009-09-01

The dental pulp undergoes age-related changes that could be ascribed to physiological, defensive, or pathological irritant-induced changes. These changes are regulated by pulp cell activity and by a variety of extracellular matrix (ECM) macromolecules, playing important roles in growth regulation, tissue differentiation and organization, formation of calcified tissue, and defense mechanisms and reactions to inflammatory stimuli. The aim of this research was to better understand the genetic changes that underlie the histological modification of the dental pulp in aging. The gene expression profile of the human dental pulp in young and older subjects was compared by RNA microarray analysis that allowed to simultaneously analyze the expression levels of thousands of genes. Data were statistically analyzed by Significance Analysis of Microarrays (SAM) Ingenuity Pathway Analysis (IPA) software. Semiquantitative and real-time reverse-transcriptase polymerase chain reaction analyses were performed to confirm the results. Microarray analysis revealed several differentially expressed genes that were categorized in growth factors, transcription regulators, apoptosis regulators, and genes of the ECM. The comparison analysis showed a high expression level of the biological functions of cell and tissue differentiation, development, and proliferation and of the immune, lymphatic, and hematologic system in young dental pulp, whereas the pathway of apoptosis was highly expressed in older dental pulp. Expression profile analyses of human dental pulp represent a sensible and useful tool for the study of mechanisms involved in differentiation, growth and aging of human dental pulp in physiological and pathological conditions.

Genome and Epigenome Editing in Mechanistic Studies of Human Aging and Aging-Related Disease.

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Lau, Cia-Hin; Suh, Yousin

2017-01-01

The recent advent of genome and epigenome editing technologies has provided a new paradigm in which the landscape of the human genome and epigenome can be precisely manipulated in their native context. Genome and epigenome editing technologies can be applied to many aspects of aging research and offer the potential to develop novel therapeutics against age-related diseases. Here, we discuss the latest technological advances in the CRISPR-based genome and epigenome editing toolbox, and provide insight into how these synthetic biology tools could facilitate aging research by establishing in vitro cell and in vivo animal models to dissect genetic and epigenetic mechanisms underlying aging and age-related diseases. We discuss recent developments in the field with the aims to precisely modulate gene expression and dynamic epigenetic landscapes in a spatial and temporal manner in cellular and animal models, by complementing the CRISPR-based editing capability with conditional genetic manipulation tools including chemically inducible expression systems, optogenetics, logic gate genetic circuits, tissue-specific promoters, and the serotype-specific adeno-associated virus. We also discuss how the combined use of genome and epigenome editing tools permits investigators to uncover novel molecular pathways involved in the pathophysiology and etiology conferred by risk variants associated with aging and aging-related disease. A better understanding of the genetic and epigenetic regulatory mechanisms underlying human aging and age-related disease will significantly contribute to the developments of new therapeutic interventions for extending health span and life span, ultimately improving the quality of life in the elderly populations. © 2016 S. Karger AG, Basel.

Gender effects on age-related changes in brain structure.

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Xu, J; Kobayashi, S; Yamaguchi, S; Iijima, K; Okada, K; Yamashita, K

2000-01-01

Previous reports have suggested that brain atrophy is associated with aging and that there are gender differences in brain atrophy with aging. These reports, however, neither exclude silent brain lesions in "healthy subjects" nor divide the brain into subregions. The aim of this study is to clarify the effect of gender on age-related changes in brain subregions by MR imaging. A computer-assisted system was used to calculate the brain matter area index (BMAI) of various regions of the brain from MR imaging of 331 subjects without brain lesions. There was significantly more brain atrophy with aging in the posterior parts of the right frontal lobe in male subjects than there was in female subjects. Age-related atrophy in the middle part of the right temporal lobe, the left basal ganglia, the parietal lobe, and the cerebellum also was found in male subjects, but not in female subjects. In the temporal lobe, thalamus, parieto-occipital lobe, and cerebellum, brain volume in the left hemisphere is significantly smaller than in the right hemisphere; sex and age did not affect the hemisphere differences of brain volume in these regions. The effect of gender on brain atrophy with aging varied in different subregions of the brain. There was more brain atrophy with aging in male subjects than in female subjects.

Low Vision Depression Prevention Trial in Age-Related Macular Degeneration

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Rovner, Barry W.; Casten, Robin J.; Hegel, Mark T.; Massof, Robert W.; Leiby, Benjamin E.; Ho, Allen C.; Tasman, William S.

2014-01-01

Purpose To compare the efficacy of behavior activation (BA) + low vision rehabilitation (LVR) with supportive therapy (ST) + LVR to prevent depressive disorders in patients with age-related macular degeneration (AMD). Design Single-masked, attention-controlled, randomized, clinical trial with outcome assessment at 4 months. Participants Patients with AMD and subsyndromal depressive symptoms attending retina practices (n = 188). Interventions Before randomization, all subjects had 2 outpatient LVR visits, and were then randomized to in-home BA+LVR or ST+LVR. Behavior activation is a structured behavioral treatment that aims to increase adaptive behaviors and achieve valued goals. Supportive therapy is a nondirective, psychological treatment that provides emotional support and controls for attention. Main Outcome Measures The Diagnostic and Statistical Manual IV defined depressive disorder based on the Patient Health Questionnaire-9 (primary outcome), Activities Inventory, National Eye Institute Vision Function Questionnaire–25 plus Supplement (NEI-VFQ), and NEI-VFQ quality of life (secondary outcomes). Results At 4 months, 11 BA+LVR subjects (12.6%) and 18 ST+LVR subjects (23.4%) developed a depressive disorder (relative risk [RR], 0.54; 95% CI, 0.27–1.06; P = 0.067). In planned adjusted analyses the RR was 0.51 (95% CI, 0.27–0.98; P = 0.04). A mediational analysis suggested that BA+LVR prevented depression to the extent that it enabled subjects to remain socially engaged. In addition, BA+LVR was associated with greater improvements in functional vision than ST+LVR, although there was no significant between-group difference. There was no significant change or between-group difference in quality of life. Conclusions An integrated mental health and low vision intervention halved the incidence of depressive disorders relative to standard outpatient LVR in patients with AMD. As the population ages, the number of persons with AMD and the adverse effects of comorbid

Sodium lauryl sulfate-induced irritation in the human face: regional and age-related differences.

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Marrakchi, S; Maibach, H I

2006-01-01

The particular sensitivity of the human face to care products prompted us to study irritation induced by sodium lauryl sulfate (SLS) in its various regions. We examined regional and age-related differences, correlating basal transepidermal water loss (TEWL) and capacitance to SLS irritation. SLS (2% aq.) was applied under occlusion for 1 h to the forehead, cheek, nose, nasolabial and perioral areas, chin, neck and forearm to two groups of subjects--one with 10 subjects with an average age of 25.2 +/- 4.7 years and another with 10 subjects with an average age of 73.7 +/- 3.9 years. TEWL was measured before and 1 h and 23 h after patch removal. Baseline stratum corneum hydration was also measured. Irritation was assessed by the changes in TEWL (deltaTEWL = TEWL after patch removal - basal TEWL) after corrections to the control. In the younger group, all areas of the face and the neck reacted to SLS, whereas the forearm did not. In the older group, the nose, perioral area and forearm did not react. In both age groups, some significant differences between the regions of the face were detected. The younger group showed higher changes in TEWL than the older group in all the areas studied, but only in the chin and nasolabial area were the differences statistically significant. Significant correlations were found between basal TEWL and deltaTEWL in 5 of the 7 areas which reacted to SLS. Baseline TEWL is one parameter that correlates with the susceptibility of the face to this irritant. 2006 S. Karger AG, Basel

Gender differences in the relative age effect among US olympic development program youth soccer players.

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Vincent, John; Glamser, Francis D

2006-04-01

A large body of research has shown that a disproportionate number of elite youth male soccer players competing in age-segmented competition are born early in the selection year. The advantage of being born early in a cohort has been termed the "relative age effect". Although there has been an exponential growth in women's soccer, few studies have examined the relative age effect in female youth soccer. This study compared the relative age effect of 1,344 female and male youth soccer players considered by the US Olympic Development Program (ODP), in 2001, to be the most talented soccer players born in 1984. The birth dates were taken from the women's state and regional ODP, and national team rosters, and were analysed using basic descriptive statistics and chi-square tests. Results revealed only a marginal relative age effect for female ODP regional and national team players and no relative age effect for female ODP state team players. In comparison, a strong relative age effect was found in male state, regional and national team players. The results suggest that there are gender differences in the relative age effect of 17-year-old elite female and male soccer players. The gender differences may be explained by a complex interaction of biological and maturational differences with socialization influences.

Age-related cerebral white matter changes on computed tomography

International Nuclear Information System (INIS)

Fukuda, Hitoshi; Kobayashi, Shotai; Koide, Hiromi; Yamaguchi, Shuhei; Okada, Kazunori; Shimote, Kouichi; Tsunematsu, Tokugoro

1989-01-01

Changes of cerebral white matter on computed cranial tomography related to aging were studied in 70 subjects aged 30 to 94 years. The subjects had no histories of cerebrovascular accidents and no abnormalities in the central nervous system were shown by physical examinations and CT scans. We measured the average attenuation values (CT numbers) of each elliptical region (165 pixels, 0.39cm 2 ) in the bilateral thalamus and twelve areas of deep white matter. Multiple regression analysis was used to assess the effects of age, cranial size and cranial bone CT numbers on the brain CT numbers. We also studied the association between brain CT numbers and brain atrophy, hypertension, diabetes mellitus. CT numbers of frontal white matter surrounding anterior horns decreased with aging in 70 subjects aged 30 to 94 years. No significant correlation between age and brain CT numbers was found in any other region by multivariate analysis, because of the prominent effect of cranial bone CT numbers on brain CT numbers. Although no age-related changes of white matter CT numbers was found in 41 subjects aged 30 to 65 years, there were significant negative correlations between age and white matter CT numbers at all regions in 29 subjects aged 66 to 94 years. Brain atrophy was associated with brain CT numbers. No association was found for hypertension or diabetes mellitus. Brain CT numbers decreased with aging even in neurologically healthy persons in older age. Brain CT numbers also decreased as cerebral atrophy advanced. (author)

Age-related cerebral white matter changes on computed tomography

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Fukuda, Hitoshi; Kobayashi, Shotai; Koide, Hiromi; Yamaguchi, Shuhei; Okada, Kazunori; Shimote, Kouichi; Tsunematsu, Tokugoro

1989-01-01

Changes of cerebral white matter on computed cranial tomography related to aging were studied in 70 subjects aged 30 to 94 years. The subjects had no histories of cerebrovascular accidents and no abnormalities in the central nervous system were shown by physical examinations and CT scans. We measured the average attenuation values (CT numbers) of each elliptical region (165 pixels, 0.39cm/sup 2/) in the bilateral thalamus and twelve areas of deep white matter. Multiple regression analysis was used to assess the effects of age, cranial size and cranial bone CT numbers on the brain CT numbers. We also studied the association between brain CT numbers and brain atrophy, hypertension, diabetes mellitus. CT numbers of frontal white matter surrounding anterior horns decreased with aging in 70 subjects aged 30 to 94 years. No significant correlation between age and brain CT numbers was found in any other region by multivariate analysis, because of the prominent effect of cranial bone CT numbers on brain CT numbers. Although no age-related changes of white matter CT numbers was found in 41 subjects aged 30 to 65 years, there were significant negative correlations between age and white matter CT numbers at all regions in 29 subjects aged 66 to 94 years. Brain atrophy was associated with brain CT numbers. No association was found for hypertension or diabetes mellitus. Brain CT numbers decreased with aging even in neurologically healthy persons in older age. Brain CT numbers also decreased as cerebral atrophy advanced. (author).

Of goals and habits: Age-related and individual differences in goal-directed decision-making

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Ben eEppinger

2013-12-01

Full Text Available In this study we investigated age-related and individual differences in habitual (model-free and goal-directed (model-based decision-making. Specifically, we were interested in three questions. First, does age affect the balance between model-based and model-free decision mechanisms? Second, are these age-related changes due to age differences in working memory (WM capacity? Third, can model-based behavior be affected by manipulating the distinctiveness of the reward value of choice options? To answer these questions we used a two-stage Markov decision task in in combination with computational modeling to dissociate model-based and model-free decision mechanisms. To affect model-based behavior in this task we manipulated the distinctiveness of reward probabilities of choice options. The results show age-related deficits in model-based decision-making, which are particularly pronounced if unexpected reward indicates the need for a shift in decision strategy. In this situation younger adults explore the task structure, whereas older adults show perseverative behavior. Consistent with previous findings, these results indicate that older adults have deficits in the representation and updating of expected reward value. We also observed substantial individual differences in model-based behavior. In younger adults high WM capacity is associated with greater model-based behavior and this effect is further elevated when reward probabilities are more distinct. However, in older adults we found no effect of WM capacity. Moreover, age differences in model-based behavior remained statistically significant, even after controlling for WM capacity. Thus, factors other than decline in WM, such as deficits in the in the integration of expected reward value into strategic decisions may contribute to the observed impairments in model-based behavior in older adults.

Prostate cancer risk: the significance of differences in age related changes in serum conjugated and unconjugated steroid hormone concentrations between Arab and Caucasian men.

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Kehinde, E O; Akanji, A O; Memon, A; Bashir, A A; Daar, A S; Al-Awadi, K A; Fatinikun, T

2006-01-01

Factors responsible for the low incidence of clinical prostate cancer (3-8/100,000 men/year) in the Arab population remain unclear, but may be related to changes in steroid hormone metabolism. We compared the levels of serum conjugated and unconjugated steroids between Arab and Caucasian populations, to determine if these can provide a rational explanation for differences in incidence of prostate cancer between the two populations. Venous blood samples were obtained from 329 unselected apparently healthy indigenous Arab men (Kuwaitis and Omanis) aged 15-80 years. Samples were also obtained from similar Arab men with newly diagnosed prostate cancer or benign prostatic hyperplasia (BPH). The samples were taken between 8:00 am and 12:00 noon. Serum levels of total testosterone, (TT), sex hormone binding globulin (SHBG), free androgen index (FAI); adrenal C19-steroids, dehydroepiandrosterone sulphate (DHEAS) and androstenedione (ADT) were determined using Immulite kits (Diagnostic Systems Laboratories Inc, Webster Texas, USA). The results obtained in Arab men were compared with those reported for similarly aged Chinese, German and White USA men. In all four ethnic groups, median TT and FAI declined with age, while SHBG increased with age. However, the mean TT and SHBG was significantly lower (p Arab men (p Arabs (p Arabs. There was no significant difference in mean serum levels of DHEAS between German and USA men. Similarly, there was no significant difference in the level of the hormones between Arab and Chinese men. Arab men with newly diagnosed prostate cancer had high serum TT, SHBG and DHEAS compared to those without the disease. The mean TT and SHBG was significantly lower in Arab men compared to Caucasian men especially in early adulthood. Caucasians have significantly higher serum levels of the precursor androgens DHEAS and ADT especially in early adulthood compared to Arab men. These observations of low circulating androgens and their adrenal precursors in

Association between SERPING1 rs2511989 polymorphism and age-related macular degeneration: Meta-analysis

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Yi Dong

2015-04-01

Full Text Available AIM: To investigate the association between SERPING1 rs2511989 (G>A polymorphism and age-related macular degeneration (AMD. METHODS: A number of electronic databases (up to July 15, 2014 were searched independently by two investigators. A Meta-analysis was performed on the association between SERPING1 rs2511989 polymorphism and AMD. Pooled odds ratios (ORs with 95% confidence intervals (CIs were estimated. RESULTS: Eight studies with 16 cohorts consisting of 9163 cases and 6813 controls were included in this Meta-analysis. There was no significant association between rs2511989 polymorphism and AMD under all genetic models in overall estimates (A vs G: OR= 0.938, 95%CI =0.858-1.025; AA vs GG:OR =0.871, 95%CI =0.719-1.056; AG vs GG: OR =0.944, 95%CI =0.845-1.054; AA+AG vs GG: OR =0.927, 95% CI =0.823-1.044; AA vs AG+GG: OR =0.890, 95%CI =0.780-1.034. Cumulative Meta-analyses also showed a trend of no association between rs2511989 polymorphism and AMD as information accumulated by year. Subgroup analysis and Meta-regression analysis indicated that age-matching status was the main source of heterogeneity. Sensitivity analysis found the results in overall comparisons and subgroup comparisons of white subjects under the allele model were found to have significantly statistical differences after studies deviating from Hardy-Weinberg equilibrium (HWE were excluded (overall: OR=0.918, 95%CI = 0.844-0.999, P =0.049; whites: OR =0.901, 95%CI = 0.817-0.994, P =0.038. However, the results were not sufficiently robust for further sensitivity analysis and statistical differences disappeared on applying Bonferroni correction (with a significance level set at 0.05/25. CONCLUSION: This Meta-analysis indicates that SERPING1 rs2511989 polymorphism and AMD tend to have no association with each other. Age matching status is a big confounding factor, and more studies with subtle designs are warranted in future.

Does Relative Age Affect Career Length in North American Professional Sports?

Science.gov (United States)

Steingröver, C; Wattie, N; Baker, J; Schorer, J

Relative age effects (RAEs) typically favour older members within a cohort; however, research suggests that younger players may experience some long-term advantages, such as longer career length. The purposes of this study were to replicate previous findings on RAEs among National Hockey League (NHL) ice hockey players, National Basketball Association (NBA) basketball players and National Football League (NFL) football players and to investigate the influence of relative age on career length in all three sports. Using official archives, birthdates and number of games played were collected for players drafted into the NBA ( N  = 407), NFL ( N  = 2380) and NHL ( N  = 1028) from 1980 to 1989. We investigated the possibility that younger players might be able to maximize their career length by operationalizing career length as players' number of games played throughout their careers. There was a clear RAE for the NHL, but effects were not significant for the NBA or NFL. Moreover, there was a significant difference in matches played between birth quartiles in the NHL favouring relatively younger players. There were no significant quartiles by career length effects in the NBA or NFL. The significant relationship between relative age and career length provides further support for relative age as an important constraint on expertise development in ice hockey but not basketball or football. Currently, the reason why relatively younger players have longer careers is not known. However, it may be worth exploring the influence of injury risk or the development of better playing skills.

Socioeconomic Status and Age Variations in Health-Related Quality of Life: Results From the National Health Measurement Study

Science.gov (United States)

Cherepanov, Dasha; Palta, Mari; Dunham, Nancy Cross; Feeny, David; Fryback, Dennis G.

2009-01-01

Objectives We examine whether multiple health-related quality of life (HRQoL) measures are stratified by socioeconomic status (SES) and age in the United States. Methods Data are from the 2005/2006 National Health Measurement Study, a telephone survey of a nationally representative sample of U.S. adults. We plot mean HRQoL scores by SES within age groups. Regression analyses test whether education, income, and assets each have independent associations with three “preference-based” HRQoL measures and self-rated health (SRH). We test whether these associations vary by age. Results There are SES disparities in HRQoL and SRH among adults in the United States at all age groups. Income differentials in HRQoL are strong across current adult age cohorts, except the 75–89 age cohort. Education and assets have statistically significant but weaker associations with HRQoL. All three SES measures are associated with SRH (net of each other) at every age group. Those in the lowest income and education groups in the 35–44 age cohort have worse HRQoL and SRH than those in higher SES groups in the 65+ age cohort. Discussion Significant improvements in HRQoL at the population level will only be possible if we improve the HRQoL of people at the lowest end of the socioeconomic distribution. PMID:19307286

The relative age effect in sport: a developmental systems model.

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Wattie, Nick; Schorer, Jörg; Baker, Joseph

2015-01-01

The policies that dictate the participation structure of many youth sport systems involve the use of a set selection date (e.g. 31 December), which invariably produces relative age differences between those within the selection year (e.g. 1 January to 31 December). Those born early in the selection year (e.g. January) are relatively older—by as much as 12 months minus 1 day—than those born later in the selection year (e.g. December). Research in the area of sport has identified a number of significant developmental effects associated with such relative age differences. However, a theoretical framework that describes the breadth and complexity of relative age effects (RAEs) in sport does not exist in the literature. This paper reviews and summarizes the existing literature on relative age in sport, and proposes a constraints-based developmental systems model for RAEs in sport.

Statistics in the Computer Age

DEFF Research Database (Denmark)

Tjur, Tue

2011-01-01

It is a trivial observation that the computers have changed the way statistics is practiced. But has it also changed the theory of statistics and the way we teach it? I think yes—even if the changes appear to be surprisingly small in some contexts. This is an attempt to give a more detailed answer...

Age-related effects on osteoclastic activities after orthodontic tooth movement.

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Li, X; Li, M; Lu, J; Hu, Y; Cui, L; Zhang, D; Yang, Y

2016-10-01

To elucidate the effects of age on the expression levels of the receptor activator of the nuclear factor-κB ligand (RANKL) and osteoclasts in the periodontal ligament during orthodontic mechanical loading and post-orthodontic retention. The study included 20 male Sprague-Dawley rats, ten in the young group (aged four to five weeks) and ten in the adult group (aged 18 to 20 weeks). In each rat, the upper-left first molar was subjected to a seven-day orthodontic force loading followed by a seven-day retention period. The upper-right first molar served as a control. The amount of orthodontic tooth movement was measured after seven-day force application and seven-day post-orthodontic retention. The expression levels of RANKL and the tartrate-resistant acid phosphatase (TRAP)-positive osteoclasts were evaluated on day 7 (end of mechanical force loading) and day 14 (after seven days of post-orthodontic retention). Statistical analysis was performed using the t-test, and significance was set at p 0.05) after the seven-day force application. On the compression side, the expression of RANKL and TRAP-positive osteoclasts in both the young and the adult groups increased after the application of force for seven days, and then decreased at the end of the seven-day retention period. However, by the end of the period, the expression of RANKL on the compression side dropped to the control level in the young group (p > 0.05), while it was still higher than that on the control side in the adult group (p 0.05), but it was significantly higher in the adult group than that in the young group after seven-day post-orthodontic retention (p Cite this article: X. Li, M. Li, J. Lu, Y. Hu, L. Cui, D. Zhang, Y. Yang. Age-related effects on osteoclastic activities after orthodontic tooth movement. Bone Joint Res 2016;5:492-499. DOI: 10.1302/2046-3758.510.BJR-2016-0004.R2. © 2016 Li et al.

Age-related oral changes.

LENUS (Irish Health Repository)

Mckenna, Gerald

2010-10-01

Age-related oral changes are seen in the oral hard and soft tissues as well as in bone, the temporomandibular joints and the oral mucosa. As older patients retain their natural teeth for longer, the clinical picture consists of normal physiological age changes in combination with pathological and iatrogenic effects. Clinical Relevance: With an ageing population retaining more of its natural teeth for longer, dental professionals should expect to observe oral age changes more frequently.

Age-related deterioration of rod vision in mice.

Science.gov (United States)

Kolesnikov, Alexander V; Fan, Jie; Crouch, Rosalie K; Kefalov, Vladimir J

2010-08-18

Even in healthy individuals, aging leads to deterioration in visual acuity, contrast sensitivity, visual field, and dark adaptation. Little is known about the neural mechanisms that drive the age-related changes of the retina and, more specifically, photoreceptors. According to one hypothesis, the age-related deterioration in rod function is due to the limited availability of 11-cis-retinal for rod pigment formation. To determine how aging affects rod photoreceptors and to test the retinoid-deficiency hypothesis, we compared the morphological and functional properties of rods of adult and aged B6D2F1/J mice. We found that the number of rods and the length of their outer segments were significantly reduced in 2.5-year-old mice compared with 4-month-old animals. Aging also resulted in a twofold reduction in the total level of opsin in the retina. Behavioral tests revealed that scotopic visual acuity and contrast sensitivity were decreased by twofold in aged mice, and rod ERG recordings demonstrated reduced amplitudes of both a- and b-waves. Sensitivity of aged rods determined from single-cell recordings was also decreased by 1.5-fold, corresponding to not more than 1% free opsin in these photoreceptors, and kinetic parameters of dim flash response were not altered. Notably, the rate of rod dark adaptation was unaffected by age. Thus, our results argue against age-related deficiency of 11-cis-retinal in the B6D2F1/J mouse rod visual cycle. Surprisingly, the level of cellular dark noise was increased in aged rods, providing an alternative mechanism for their desensitization.

Technical issues relating to the statistical parametric mapping of brain SPECT studies

International Nuclear Information System (INIS)

Hatton, R.L.; Cordato, N.; Hutton, B.F.; Lau, Y.H.; Evans, S.G.

2000-01-01

Full text: Statistical Parametric Mapping (SPM) is a software tool designed for the statistical analysis of functional neuro images, specifically Positron Emission Tomography and functional Magnetic Resonance Imaging, and more recently SPECT. This review examines some problems associated with the analysis of SPECT. A comparison of a patient group with normal studies revealed factors that could influence results, some that commonly occur, others that require further exploration. To optimise the differences between two groups of subjects, both spatial variability and differences in global activity must be minimised. The choice and effectiveness of co registration method and approach to normalisation of activity concentration can affect the optimisation. A small number of subject scans were identified as possessing truncated data resulting in edge effects that could adversely influence the analysis. Other problems included unusual areas of significance possibly related to reconstruction methods and the geometry associated with nonparallel collimators. Areas of extra cerebral significance are a point of concern - and may result from scatter effects, or mis registration. Difficulties in patient positioning, due to postural limitations, can lead to resolution differences. SPM has been used to assess areas of statistical significance arising from these technical factors, as opposed to areas of true clinical significance when comparing subject groups. This contributes to a better understanding of the effects of technical factors so that these may be eliminated, minimised, or incorporated in the study design. Copyright (2000) The Australian and New Zealand Society of Nuclear Medicine Inc

Age-related incidence of pulmonary embolism and additional pathologic findings detected by computed tomography pulmonary angiography

Energy Technology Data Exchange (ETDEWEB)

Groth, M., E-mail: groth.michael@googlemail.com [Center for Radiology and Endoscopy, Department of Diagnostic and Interventional Radiology, University Medical Center Hamburg-Eppendorf, Martinistr. 52, 20246 Hamburg (Germany); Henes, F.O., E-mail: f.henes@uke.uni-hamburg.de [Center for Radiology and Endoscopy, Department of Diagnostic and Interventional Radiology, University Medical Center Hamburg-Eppendorf, Martinistr. 52, 20246 Hamburg (Germany); Mayer, U., E-mail: mayer@uke.uni-hamburg.de [Emergency Department, University Medical Center Hamburg-Eppendorf, Martinistr. 52, 20246 Hamburg (Germany); Regier, M., E-mail: m.regier@uke.uni-hamburg.de [Center for Radiology and Endoscopy, Department of Diagnostic and Interventional Radiology, University Medical Center Hamburg-Eppendorf, Martinistr. 52, 20246 Hamburg (Germany); Adam, G., E-mail: g.adam@uke.uni-hamburg.de [Center for Radiology and Endoscopy, Department of Diagnostic and Interventional Radiology, University Medical Center Hamburg-Eppendorf, Martinistr. 52, 20246 Hamburg (Germany); Begemann, P.G.C., E-mail: p.begemann@me.com [Center for Radiology and Endoscopy, Department of Diagnostic and Interventional Radiology, University Medical Center Hamburg-Eppendorf, Martinistr. 52, 20246 Hamburg (Germany)

2012-08-15

Objective: To compare the incidence of pulmonary embolism (PE) and additional pathologic findings (APF) detected by computed tomography pulmonary angiography (CTPA) according to different age-groups. Materials and methods: 1353 consecutive CTPA cases for suspected PE were retrospectively reviewed. Patients were divided into seven age groups: {<=}29, 30-39, 40-49, 50-59, 60-69, 70-79 and {>=}80 years. Differences between the groups were tested using Fisher's exact or chi-square test. A p-value < 0.0024 indicated statistical significance when Bonferroni correction was used. Results: Incidence rates of PE ranged from 11.4% to 25.4% in different age groups. The three main APF were pleural effusion, pneumonia and pulmonary nodules. No significant difference was found between the incidences of PE in different age groups. Furthermore, APF in different age groups revealed no significant differences (all p-values > 0.0024). Conclusion: The incidences of PE and APF detected by CTPA reveal no significant differences between various age groups.

Gene-diet interactions in age-related macular degeneration

Science.gov (United States)

Age-related macular degeneration (AMD) is a prevalent blinding disease, accounting for roughly 50% of blindness in developed nations. Very significant advances have been made in terms of discovering genetic susceptibilities to AMD as well as dietary risk factors. To date, nutritional supplementation...

Confounding and Statistical Significance of Indirect Effects: Childhood Adversity, Education, Smoking, and Anxious and Depressive Symptomatology

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Mashhood Ahmed Sheikh

2017-08-01

Full Text Available The life course perspective, the risky families model, and stress-and-coping models provide the rationale for assessing the role of smoking as a mediator in the association between childhood adversity and anxious and depressive symptomatology (ADS in adulthood. However, no previous study has assessed the independent mediating role of smoking in the association between childhood adversity and ADS in adulthood. Moreover, the importance of mediator-response confounding variables has rarely been demonstrated empirically in social and psychiatric epidemiology. The aim of this paper was to (i assess the mediating role of smoking in adulthood in the association between childhood adversity and ADS in adulthood, and (ii assess the change in estimates due to different mediator-response confounding factors (education, alcohol intake, and social support. The present analysis used data collected from 1994 to 2008 within the framework of the Tromsø Study (N = 4,530, a representative prospective cohort study of men and women. Seven childhood adversities (low mother's education, low father's education, low financial conditions, exposure to passive smoke, psychological abuse, physical abuse, and substance abuse distress were used to create a childhood adversity score. Smoking status was measured at a mean age of 54.7 years (Tromsø IV, and ADS in adulthood was measured at a mean age of 61.7 years (Tromsø V. Mediation analysis was used to assess the indirect effect and the proportion of mediated effect (% of childhood adversity on ADS in adulthood via smoking in adulthood. The test-retest reliability of smoking was good (Kappa: 0.67, 95% CI: 0.63; 0.71 in this sample. Childhood adversity was associated with a 10% increased risk of smoking in adulthood (Relative risk: 1.10, 95% CI: 1.03; 1.18, and both childhood adversity and smoking in adulthood were associated with greater levels of ADS in adulthood (p < 0.001. Smoking in adulthood did not significantly

Metabolic syndrome but not obesity measures are risk factors for accelerated age-related glomerular filtration rate decline in the general population.

Science.gov (United States)

Stefansson, Vidar T N; Schei, Jørgen; Solbu, Marit D; Jenssen, Trond G; Melsom, Toralf; Eriksen, Bjørn O

2018-05-01

Rapid age-related glomerular filtration rate (GFR) decline increases the risk of end-stage renal disease, and a low GFR increases the risk of mortality and cardiovascular disease. High body mass index and the metabolic syndrome are well-known risk factors for patients with advanced chronic kidney disease, but their role in accelerating age-related GFR decline independent of cardiovascular disease, hypertension and diabetes is not adequately understood. We studied body mass index, waist circumference, waist-hip ratio and metabolic syndrome as risk factors for accelerated GFR decline in 1261 middle-aged people representative of the general population without diabetes, cardiovascular disease or kidney disease. GFR was measured as iohexol clearance at baseline and repeated after a median of 5.6 years. Metabolic syndrome was defined as fulfilling three out of five criteria, based on waist circumference, blood pressure, glucose, high-density lipoprotein cholesterol and triglycerides. The mean GFR decline rate was 0.95 ml/min/year. Neither the body mass index, waist circumference nor waist-hip ratio predicted statistically significant changes in age-related GFR decline, but individuals with baseline metabolic syndrome had a significant mean of 0.30 ml/min/year faster decline than individuals without metabolic syndrome in a multivariable adjusted linear regression model. This association was mainly driven by the triglyceride criterion of metabolic syndrome, which was associated with a significant 0.36 ml/min/year faster decline when analyzed separately. Results differed significantly when GFR was estimated using creatinine and/or cystatin C. Thus, metabolic syndrome, but not the body mass index, waist circumference or waist-hip ratio, is an independent risk factor for accelerated age-related GFR decline in the general population. Copyright © 2017 International Society of Nephrology. Published by Elsevier Inc. All rights reserved.

Worry, Intolerance of Uncertainty, and Statistics Anxiety

Science.gov (United States)

Williams, Amanda S.

2013-01-01

Statistics anxiety is a problem for most graduate students. This study investigates the relationship between intolerance of uncertainty, worry, and statistics anxiety. Intolerance of uncertainty was significantly related to worry, and worry was significantly related to three types of statistics anxiety. Six types of statistics anxiety were…

The Relative Age Effect in Spanish Female Soccer Players. Influence of the Competitive Level and a Playing Position.

Science.gov (United States)

Sedano, Silvia; Vaeyens, Roel; Redondo, Juan Carlos

2015-06-27

The purposes of the study were to examine relative age effects (RAEs) in Spanish female soccer and to identify the influence of a playing position. The sample comprised all female players (n=4035) of five different competitive levels in the 2010-2013 seasons: First, Second and Third divisions (n=936, n=1711 and n=870, respectively), and National and Regional (n=232 and n=286, respectively) teams were included. Differences between the observed and expected birth-date distributions were tested based on data from the general Spanish population, using the chi-square statistic followed up by calculating odds ratios and 95% confidence intervals. Results revealed that the birth-date distributions of almost all groups of football players showed an overrepresentation of players born in the first quartile. Only in the lowest level was age distribution not significantly different from that of the general population. Moreover, the RAE risk progressively increased with a higher level of involvement. It was also observed that at some playing positions the birth-date distributions were significantly biased. That was the case for goalkeepers and defenders. It could be concluded that in the current structure of Spanish female soccer there is a relative age effect, probably due to the early processes of talent identification.

The Relative Age Effect in Spanish Female Soccer Players. Influence of the Competitive Level and a Playing Position

Directory of Open Access Journals (Sweden)

Sedano Silvia

2015-06-01

Full Text Available The purposes of the study were to examine relative age effects (RAEs in Spanish female soccer and to identify the influence of a playing position. The sample comprised all female players (n=4035 of five different competitive levels in the 2010-2013 seasons: First, Second and Third divisions (n=936, n=1711 and n=870, respectively, and National and Regional (n=232 and n=286, respectively teams were included. Differences between the observed and expected birth-date distributions were tested based on data from the general Spanish population, using the chi-square statistic followed up by calculating odds ratios and 95% confidence intervals. Results revealed that the birth-date distributions of almost all groups of football players showed an overrepresentation of players born in the first quartile. Only in the lowest level was age distribution not significantly different from that of the general population. Moreover, the RAE risk progressively increased with a higher level of involvement. It was also observed that at some playing positions the birth-date distributions were significantly biased. That was the case for goalkeepers and defenders. It could be concluded that in the current structure of Spanish female soccer there is a relative age effect, probably due to the early processes of talent identification.

Estimation of salivary flow rate, pH, buffer capacity, calcium, total protein content and total antioxidant capacity in relation to dental caries severity, age and gender.

Science.gov (United States)

Pandey, Pallavi; Reddy, N Venugopal; Rao, V Arun Prasad; Saxena, Aditya; Chaudhary, C P

2015-03-01

The aim of the study was to evaluate salivary flow rate, pH, buffering capacity, calcium, total protein content and total antioxidant capacity in relation to dental caries, age and gender. The study population consisted of 120 healthy children aged 7-15 years that was further divided into two groups: 7-10 years and 11-15 years. In this 60 children with DMFS/dfs = 0 and 60 children with DMFS/dfs ≥5 were included. The subjects were divided into two groups; Group A: Children with DMFS/dfs = 0 (caries-free) Group B: Children with DMFS/dfs ≥5 (caries active). Unstimulated saliva samples were collected from all groups. Flow rates were determined, and samples analyzed for pH, buffer capacity, calcium, total protein and total antioxidant status. Salivary antioxidant activity is measured with spectrophotometer by an adaptation of 2,2'-azino-di-(3-ethylbenzthiazoline-6-sulphonate) assays. The mean difference of the two groups; caries-free and caries active were proved to be statistically significant (P salivary calcium, total protein and total antioxidant level for both the sexes in the age group 7-10 years and for the age 11-15 years the mean difference of the two groups were proved to be statistically significant (P salivary calcium level for both the sexes. Salivary total protein and total antioxidant level were proved to be statistically significant for male children only. In general, total protein and total antioxidants in saliva were increased with caries activity. Calcium content of saliva was found to be more in caries-free group and increased with age.

Do peer relations in adolescence influence health in adulthood? Peer problems in the school setting and the metabolic syndrome in middle-age.

Directory of Open Access Journals (Sweden)

Per E Gustafsson

Full Text Available While the importance of social relations for health has been demonstrated in childhood, adolescence and adulthood, few studies have examined the prospective importance of peer relations for adult health. The aim of this study was to examine whether peer problems in the school setting in adolescence relates to the metabolic syndrome in middle-age. Participants came from the Northern Swedish Cohort, a 27-year cohort study of school leavers (effective n = 881, 82% of the original cohort. A score of peer problems was operationalized through form teachers' assessment of each student's isolation and popularity among school peers at age 16 years, and the metabolic syndrome was measured by clinical measures at age 43 according to established criteria. Additional information on health, health behaviors, achievement and social circumstances were collected from teacher interviews, school records, clinical measurements and self-administered questionnaires. Logistic regression was used as the main statistical method. Results showed a dose-response relationship between peer problems in adolescence and metabolic syndrome in middle-age, corresponding to 36% higher odds for the metabolic syndrome at age 43 for each SD higher peer problems score at age 16. The association remained significant after adjustment for health, health behaviors, school adjustment or family circumstances in adolescence, and for psychological distress, health behaviors or social circumstances in adulthood. In analyses stratified by sex, the results were significant only in women after adjustment for covariates. Peer problems were significantly related to all individual components of the metabolic syndrome. These results suggest that unsuccessful adaption to the school peer group can have enduring consequences for metabolic health.

Age-related changes in pre- and postmenopausal women investigated with 18F-fluoride PET - a preliminary study

International Nuclear Information System (INIS)

Kurata, Seiji; Ishibashi, Masatoshi; Shizukuishi, Kazuya; Tateishi, Ukihide; Yoneyama, Tomohiro; Hino, Ayako; Inoue, Tomio

2012-01-01

To evaluate the relationship between age and regional skeletal uptake at sites consisting of either predominantly trabecular or cortical bone using 18 F-fluoride positron emission tomography (PET) in pre- and postmenopausal women. Thirty-two women (40.6 ± 12.3 years; age range 25-72 years) were assigned to one of two groups: group 1 comprised 22 premenopausal women (33 ± 6.5 years; age range 25-48 years) and group 2 comprised 10 postmenopausal women (56 ± 6.7 years; age range 49-72 years). The maximum standardized uptake value (SUVmax) was determined from the lumbar spine and the humeral shaft. Student's t-test for each unpaired dataset was used to evaluate statistical differences between the two groups. The SUVmax values for the humeral shaft and the lumbar spine were compared with aging. The SUVmax (mean ± SD) was 1.2 ± 0.5 in the humeral shaft and 4.7 ± 1.0 in the lumbar spine. The SUVmax in the humeral shaft correlated significantly with advancing age (r = 0.67, P 18 F-fluoride PET might be a useful tool for analyzing age-related changes in pre- and postmenopausal women. (orig.)

The relative age effect and success in German elite U-17 soccer teams.

Science.gov (United States)

Augste, Claudia; Lames, Martin

2011-06-01

The aim of the study was to determine whether there is empirical evidence for advantages in performance of soccer teams because of their relative age. The practice of selecting youth players according to their momentary performance leads to relative age effects, which in turn lead to inefficient talent selection. We used the median of the birth dates as a measure of the effect size of the relative age effect and the Kolmogorov-Smirnov test to assess its significance. For the 2008-2009 season, birth dates in the three German U-17 first leagues for soccer were examined (911 players). More than half of the 41 teams differed significantly from the distribution of the corresponding German cohort. There was a significant correlation between the relative age effect and success defined by teams' final rankings (Spearman's ρ = 0.328, P = 0.036). Regression analyses revealed that with a median of birth dates one month earlier the team is expected to finish 1.035 ranks better. Accordingly, selecting early born athletes is an important aspect of success in youth soccer. However, teams with no relative age effect are able to compete in the league, having the benefit to promote players with a better perspective for long and successful careers at an adult age.

Age-Related Hearing Loss in Mn-SOD Heterozygous Knockout Mice

Directory of Open Access Journals (Sweden)

Makoto Kinoshita

2013-01-01

Full Text Available Age-related hearing loss (AHL reduces the quality of life for many elderly individuals. Manganese superoxide dismutase (Mn-SOD, one of the antioxidant enzymes acting within the mitochondria, plays a crucial role in scavenging reactive oxygen species (ROS. To determine whether reduction in Mn-SOD accelerates AHL, we evaluated auditory function in Mn-SOD heterozygous knockout (HET mice and their littermate wild-type (WT C57BL/6 mice by means of auditory brainstem response (ABR. Mean ABR thresholds were significantly increased at 16 months when compared to those at 4 months in both WT and HET mice, but they did not significantly differ between them at either age. The extent of hair cell loss, spiral ganglion cell density, and thickness of the stria vascularis also did not differ between WT and HET mice at either age. At 16 months, immunoreactivity of 8-hydroxydeoxyguanosine was significantly greater in the SGC and SV in HET mice compared to WT mice, but that of 4-hydroxynonenal did not differ between them. These findings suggest that, although decrease of Mn-SOD by half may increase oxidative stress in the cochlea to some extent, it may not be sufficient to accelerate age-related cochlear damage under physiological aging process.

Intraocular pressure asymmetry is not a clinically-significant feature when using the PULSAIR non-contact tonometer.

Science.gov (United States)

Pointer, J S

1997-11-01

This report describes the results of a retrospective analysis of intraocular pressure (i.o.p.) values recorded from the right (R) and left (L) eyes of middle-aged and elderly at-risk but assumed non-glaucomatous subjects. The tensions had been measured using the Keeler PULSAIR non-contact tonometer (NCT) in the course of routine optometric practice when individuals attended for a sight test. These bilateral IOP data were collated on the basis of each subject's gender, (male/female), age (40-59 years/60+ years) and the time of the tonometry assessment (a.m./p.m.). Wherever possible material was equi-partitioned across these three bipartite variables producing balanced data groupings. Pair-wise testing of R versus L absolute values of pneumo-applanation pressures across any of the balanced data groupings failed to reveal a statistically-significant difference between the paired IOP distributions. There was a consistent but small relative IOP asymmetry (L > R) in these data. Further analysis indicated that this asymmetry only attained borderline statistical significance with respect to subject's age: neither gender nor the time of assessment were statistically significant features, and there were no statistically-significant interactions between any of the three variables. In conclusion, provided that the manufacturer's operating instructions are adhered to, IOP asymmetry is not a clinically-significant feature when using the PULSAIR NCT on a clinical population at risk of developing glaucoma.

Radiation therapy for small choroidal neovascularization in age-related macular degeneration

Energy Technology Data Exchange (ETDEWEB)

Matsuhashi, Hideaki; Noda, Yasuko; Takahashi, Daisuke; Mariya, Yasushi [Hirosaki Univ., Aomori (Japan). School of Medicine

1999-06-01

Radiation therapy for age-related macular degeneration with subfoveal or juxtafoveal choroidal neovascularization smaller than or equal to 1 disc area was evaluated. Fourteen eyes received a total radiation dose of 10-20 Gy in 5-10 fractions. The mean follow-up time was 22 months. Ten eyes in a control group were followed for an average of 16 months without any treatment. At a 12-month follow-up examination, funduscopic and angiographic findings had improved in 7 eyes (50%), were unchanged in 1 eye (7%) and, had deteriorated in 6 eyes (43%) among the treated patients. The same findings had improved in 1 eye (10%), were unchanged in 2 eyes (20%), and had deteriorated in 7 eyes (70%) among the control patients. There was a statistically significant difference by Mann-Whitney U test between the two groups. Visual acuity had improved in 4 eyes (29%), was unchanged in 6 eyes (43%), and had declined in 4 eyes (29%) among the treated patients. Among the control patients visual acuity had improved in none of the eyes (0%), was unchanged in 6 eyes (60%), and had declined in 4 eyes (40%). The difference between the two groups was not statistically significant. Of the 7 cases whose fundus had improved by 12 months, 4 cases maintained a favorable status through the following 2 years. Radiation therapy had an inhibitory effect on small choroidal neovascularization when viewed by funduscopy and angiography, but, the efficacy for visual prognosis was not always identified. (author)

Interventions for age-related diseases

DEFF Research Database (Denmark)

Figueira, Inês; Fernandes, Adelaide; Mladenovic Djordjevic, Aleksandra

2016-01-01

Over 60% of people aged over 65 are affected by multiple morbidities, which are more difficult to treat, generate increased healthcare costs and lead to poor quality of life compared to individual diseases. With the number of older people steadily increasing this presents a societal challenge. Age...... is the major risk factor for age-related diseases and recent research developments have led to the proposal that pharmacological interventions targeting common mechanisms of ageing may be able to delay the onset of multimorbidity. Here we review the state of the knowledge of multimorbidity, appraise...... the available evidence supporting the role of mechanisms of ageing in the development of the most common age-related diseases and assess potential molecules that may successfully target those key mechanisms....

Age-related changes in bone architecture.

Science.gov (United States)

Giordano, Vincenzo; Franco, José Sérgio; Koch, Hilton Augusto; Labronici, Pedro José; Pires, Robinson Esteves S; Amaral, Ney Pecegueiro DO

2016-01-01

: to evaluate the histologic and morphometric characteristics of bone biopsies of the anterior iliac crest of patients of different age groups. : we studied 30 bone samples from the iliac crest, using brightfield optical microscopy. We divided the samples by donors' age groups in three groups: Group 1 (n = 10), subjects aged between 25 and 39 years; Group 2 (n = 10), subjects aged between 40 and 64 years; Group 3 (n = 10), individuals aged 65 years and over. We randomly divided the samples into two sets with 15 specimens. In the first study segment (n = 15), we used histological to assess the osteogenic property of the graft, through the analysis of cell reserve in the periosteum, the number of osteocytes in the lacunae and the number of Haversian and Volkmann's canals. In the second study segment (n = 15), we investigated the morphology of osteoconductive property of the graft, through quantification of the trabecular meshwork (Vv) and trabecular area (Sv). : histologically, we observed degeneration of bone occurring with age, characterized by thinning of the periosteum, with gradual replacement of the steogenic layer by fibrous tissue, small amount of Haversian and Volkmann's canals, osteocyte lacunae voids and fine spongy bone trabeculae, allowing ample medullary space, usually occupied by fat cells and adipocytes. Morphologically, with respect to the quantification of the trabecular meshwork (Vv), we found statistically significant differences between Groups 1 and 3 and between Groups 2 and 3, with reduction of the trabecular meshwork of about 45% in the elderly over 65 years old ; there was no statistically significant difference between Groups 1 and 2. There was also no statistical difference between the Groups regarding Sv. : the results of this experiment suggest that, in the elderly (over 65 years old), the osteogenic property of autologous bone graft decreases and the osteoconductive property is compromised. avaliar as características histológicas e

Tissue plasminogen activator-assisted vitrectomy for submacular hemorrhage due to age-related macular degeneration

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Mustafa Gok

2017-01-01

Full Text Available Purpose: The purpose of this study was to evaluate the treatment efficacy of vitrectomy combined with subretinal recombinant tissue plasminogen activator (r-tPA and factors affecting visual improvement in patients with submacular hemorrhage (SMH due to neovascular age-related macular degeneration (nAMD. Materials and Methods: Medical records of 17 consecutive patients diagnosed with SMH secondary to nAMD were retrospectively reviewed. The initial surgical procedure involved a 23-gauge transconjunctival vitrectomy, subretinal r-tPA application through a self-sealing inferior retinotomy, and sulfur hexafluoride gas for tamponade in all patients. The duration, size, and thickness of the hemorrhage and the pre- and post-operative visual acuity (VA using a Snellen chart were recorded. VA was converted to logMAR for statistical analysis. Results: The average duration and size of the SMH were 12.8 ± 18.2 days and 8.6 ± 5.3 disc areas, respectively. The mean follow-up time was 16.9 ± 4.7 months. A statistically significant visual improvement was found when comparing initial VA with postoperative best-corrected VA (BCVA and final BCVA (Wilcoxon rank test, P ≤ 0.01. There was no significant correlation between the size of the hemorrhage and postoperative BCVA and final BCVA (Spearman's rho test. There was no statistically significant correlation between the initial VA and postoperative BCVA and final BCVA (Spearman's rho test. There was no significant correlation between the duration of hemorrhage and postoperative BCVA and final BCVA (Spearman's rho test. The preoperative thickness of hemorrhage (747.5 ± 30 μm was not correlated with postoperative BCVA or final BCVA (Pearson's test. Conclusions: Vitrectomy combined with subretinal r-tPA injection and gas tamponade is an effective surgical intervention to preserve VA in selected patients with apparent SMH.

Manipulation of Ovarian Function Significantly Influenced Sarcopenia in Postreproductive-Age Mice

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Rhett L. Peterson

2016-01-01

Full Text Available Previously, transplantation of ovaries from young cycling mice into old postreproductive-age mice increased life span. We anticipated that the same factors that increased life span could also influence health span. Female CBA/J mice received new (60 d ovaries at 12 and 17 months of age and were evaluated at 16 and 25 months of age, respectively. There were no significant differences in body weight among any age or treatment group. The percentage of fat mass was significantly increased at 13 and 16 months of age but was reduced by ovarian transplantation in 16-month-old mice. The percentages of lean body mass and total body water were significantly reduced in 13-month-old control mice but were restored in 16- and 25-month-old recipient mice by ovarian transplantation to the levels found in six-month-old control mice. In summary, we have shown that skeletal muscle mass, which is negatively influenced by aging, can be positively influenced or restored by reestablishment of active ovarian function in aged female mice. These findings provide strong incentive for further investigation of the positive influence of young ovaries on restoration of health in postreproductive females.

The period-age relation for cepheids

International Nuclear Information System (INIS)

Efremov, Yu.N.

1978-01-01

The list of 119 cepheid-members of 55 clusters and associations of the Magellanic Clouds, the Galaxy, and M31 is given. The period-age relation is found from the data on 64 cepheids in 29 clusters for which the age determinations are available, the ages of extragalactic clusters were determined mainly from their integral colours. The U-B colours are found to be of much better age parameters than the B-V ones. The composite period-age relation agrees well with the theoretical one. The observed dispersion of the period-age relation leads to an estimate of the age dispersion about 1x10 7 years in the associations. Some peculiarities of the cepheids with the shortest periods amongst others in the same clusters are probably explained if they are overtone pulsators. The period-age relation may be used for an investigation of the recent history of star formation in the galaxies. This relation allows to determine the age gradient across the spiral arm in M31 which is in agreement with the density wave theory predictions. The distribution of cepheids in our Galaxy and neighbouring galaxies is consistent with the conception of star formation lasting for some dozen million years in cells with a dimension of some hundreds of parsecs

CT MEASUREMENTS OF TWO CEREBROVENTRICULAR INDICES AND THEIR RELATION WITH AGE

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Ambili Puthanveettil

2017-01-01

Full Text Available BACKGROUND Cerebroventricular Indices are the relative measurements of the size of lateral ventricle to that of brain. A normal study of these indices are necessary in order to understand any changes in size of the ventricles or other associated abnormalities of the brain. The study uses measurements from Computerised Tomography (CT which is uniformly calibrated, has reproducible data and is less expensive than MRI. MATERIALS AND METHODS CT scans of 186 apparently healthy normal individuals of age group 1 to 85 years were taken and the subjects were categorized into age intervals of 10 years; males and females taken separately. The linear measurements of lateral ventricle and brain were taken directly from the screen. The cerebrovascular indices were calculated. The mean values in each group were compared with age and sex, using appropriate statistical tests. RESULTS Mean value for Bifrontal index was 0.31±0.03 and that of Bicaudate index was 0.12±0.02. Both indices showed a positive correlation with age. The relative size of the lateral ventricle with the brain did not show any gender difference. CONCLUSION The study results coincide with previous similar studies. Both the indices showed positive correlation with age, of which the Bicaudate index was more sensitive.

Cystic Lesions in the Greater Tuberosity of the Humerus: The Relation to Rotator Cuff Tears and Age

International Nuclear Information System (INIS)

Kim, Gang Deuk; Oh, Jung Taek

2008-01-01

This study was designed to investigate the location of cystic lesions in the greater tuberosity of the humerus and the relationship to rotator cuff tears and age. A total of 78 patients (age range, 19-82 years; mean age, 51 years) who underwent arthroscopy or open surgery after MR arthrography (MRA) for a painful shoulder were enrolled in the study. The location of the cystic lesions were classified as 'A' for a supraspinatus insertion site, as 'C' for an infraspinatus insertion site, as 'B' for both a supraspinatus and infraspinatus insertion site, as 'BG' for a site posterior to the bicipital groove and as 'P' for a site at the bare area of the humeral head. The location of cystic lesions and supraspinatus and infraspinatus tears were evaluated on MRA. Statistical analyses used the chi-squared test and logistic regression. 'BG' and 'A' cystic lesions were related to the presence of a supraspinatus tear, 'C' cystic lesions were related to the presence of an infraspinatus tear and 'B' cystic lesions were related to the presence of both supraspinatus and infraspinatus tears (p < 0.05). 'P' cystic lesions were not related to the presence of rotator cuff tears. The incidence of cystic lesions increased with age, but with no statistical correlation. Cystic lesions at the supraspinatus and infraspinatus insertion sites are useful to predict the presence of a rotator cuff tear, but cystic lesions were not age related

The Importance of Integrating Clinical Relevance and Statistical Significance in the Assessment of Quality of Care--Illustrated Using the Swedish Stroke Register.

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Anita Lindmark

Full Text Available When profiling hospital performance, quality inicators are commonly evaluated through hospital-specific adjusted means with confidence intervals. When identifying deviations from a norm, large hospitals can have statistically significant results even for clinically irrelevant deviations while important deviations in small hospitals can remain undiscovered. We have used data from the Swedish Stroke Register (Riksstroke to illustrate the properties of a benchmarking method that integrates considerations of both clinical relevance and level of statistical significance.The performance measure used was case-mix adjusted risk of death or dependency in activities of daily living within 3 months after stroke. A hospital was labeled as having outlying performance if its case-mix adjusted risk exceeded a benchmark value with a specified statistical confidence level. The benchmark was expressed relative to the population risk and should reflect the clinically relevant deviation that is to be detected. A simulation study based on Riksstroke patient data from 2008-2009 was performed to investigate the effect of the choice of the statistical confidence level and benchmark value on the diagnostic properties of the method.Simulations were based on 18,309 patients in 76 hospitals. The widely used setting, comparing 95% confidence intervals to the national average, resulted in low sensitivity (0.252 and high specificity (0.991. There were large variations in sensitivity and specificity for different requirements of statistical confidence. Lowering statistical confidence improved sensitivity with a relatively smaller loss of specificity. Variations due to different benchmark values were smaller, especially for sensitivity. This allows the choice of a clinically relevant benchmark to be driven by clinical factors without major concerns about sufficiently reliable evidence.The study emphasizes the importance of combining clinical relevance and level of statistical

The Importance of Integrating Clinical Relevance and Statistical Significance in the Assessment of Quality of Care--Illustrated Using the Swedish Stroke Register.

Science.gov (United States)

Lindmark, Anita; van Rompaye, Bart; Goetghebeur, Els; Glader, Eva-Lotta; Eriksson, Marie

2016-01-01

When profiling hospital performance, quality inicators are commonly evaluated through hospital-specific adjusted means with confidence intervals. When identifying deviations from a norm, large hospitals can have statistically significant results even for clinically irrelevant deviations while important deviations in small hospitals can remain undiscovered. We have used data from the Swedish Stroke Register (Riksstroke) to illustrate the properties of a benchmarking method that integrates considerations of both clinical relevance and level of statistical significance. The performance measure used was case-mix adjusted risk of death or dependency in activities of daily living within 3 months after stroke. A hospital was labeled as having outlying performance if its case-mix adjusted risk exceeded a benchmark value with a specified statistical confidence level. The benchmark was expressed relative to the population risk and should reflect the clinically relevant deviation that is to be detected. A simulation study based on Riksstroke patient data from 2008-2009 was performed to investigate the effect of the choice of the statistical confidence level and benchmark value on the diagnostic properties of the method. Simulations were based on 18,309 patients in 76 hospitals. The widely used setting, comparing 95% confidence intervals to the national average, resulted in low sensitivity (0.252) and high specificity (0.991). There were large variations in sensitivity and specificity for different requirements of statistical confidence. Lowering statistical confidence improved sensitivity with a relatively smaller loss of specificity. Variations due to different benchmark values were smaller, especially for sensitivity. This allows the choice of a clinically relevant benchmark to be driven by clinical factors without major concerns about sufficiently reliable evidence. The study emphasizes the importance of combining clinical relevance and level of statistical confidence when

The relative age effect in a professional football club setting.

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Mujika, Iñigo; Vaeyens, Roel; Matthys, Stijn P J; Santisteban, Juanma; Goiriena, Juan; Philippaerts, Renaat

2009-09-01

The relative age effect is an uneven distribution of birth date favouring subjects born in the initial months of a selection year. This study compared the birth-date distributions between several subgroups of Basque football players to identify whether the relative age effect is influenced by age and/or skill level. The study comprised 13,519 players including 114 senior professionals from the Spanish league's AC Bilbao over 21 seasons; over the season 2005-2006, it comprised elite youth (n=189) from the same club's academy; regional youth (n=4382) U11-U14 locally federated players; school youth (n=8834) U10-U11 locally registered school district players. Differences between the observed and expected birth-date distributions were tested based on data from the general Basque male population. Significant chi-square values were followed up by calculating odds ratios and 95% confidence intervals (CI) for the quartile and half-year distributions to examine subgroup differences in the relative age effect. Birth-date distributions of all groups of players showed a significant bias towards early birth in the selection year compared with the reference population (senior, chi-2(3) = 24.4, P talent.

Intensive inpatient treatment for bulimia nervosa: Statistical and clinical significance of symptom changes.

Science.gov (United States)

Diedrich, Alice; Schlegl, Sandra; Greetfeld, Martin; Fumi, Markus; Voderholzer, Ulrich

2018-03-01

This study examines the statistical and clinical significance of symptom changes during an intensive inpatient treatment program with a strong psychotherapeutic focus for individuals with severe bulimia nervosa. 295 consecutively admitted bulimic patients were administered the Structured Interview for Anorexic and Bulimic Syndromes-Self-Rating (SIAB-S), the Eating Disorder Inventory-2 (EDI-2), the Brief Symptom Inventory (BSI), and the Beck Depression Inventory-II (BDI-II) at treatment intake and discharge. Results indicated statistically significant symptom reductions with large effect sizes regarding severity of binge eating and compensatory behavior (SIAB-S), overall eating disorder symptom severity (EDI-2), overall psychopathology (BSI), and depressive symptom severity (BDI-II) even when controlling for antidepressant medication. The majority of patients showed either reliable (EDI-2: 33.7%, BSI: 34.8%, BDI-II: 18.1%) or even clinically significant symptom changes (EDI-2: 43.2%, BSI: 33.9%, BDI-II: 56.9%). Patients with clinically significant improvement were less distressed at intake and less likely to suffer from a comorbid borderline personality disorder when compared with those who did not improve to a clinically significant extent. Findings indicate that intensive psychotherapeutic inpatient treatment may be effective in about 75% of severely affected bulimic patients. For the remaining non-responding patients, inpatient treatment might be improved through an even stronger focus on the reduction of comorbid borderline personality traits.

Ultra-widefield fundus autofluorescence in age-related macular degeneration.

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Abhilash Guduru

Full Text Available Establish accuracy and reproducibility of subjective grading in ultra-widefield fundus autofluorescence (FAF imaging in patients with age-related macular degeneration (AMD, and determine if an association exists between peripheral FAF abnormalities and AMD.This was a prospective, single-blinded case-control study. Patients were consecutively recruited for the study. Patients were excluded if there was a history of prior or active ocular pathology other than AMD or image quality was insufficient for analysis as determined by two independent graders. Control patients were those without any evidence of AMD or other ophthalmic disease apart from cataract. Using the Optos 200Tx (Optos, Marlborough, MA, USA, a ResMax central macula and an ultra-widefield peripheral retina image was taken for each eye in both normal color and short wavelength FAF. Ultra-widefield photographs were modified to mask the macula. Each ResMax and ultra-widefield image was independently graded by two blinded investigators.There were 28 AMD patients and 11 controls. There was a significant difference in the average age between AMD patients and control groups (80 versus 64, respectively P<0.001. There was moderate, statistically significant agreement between observers regarding image interpretation (78.4%, K = 0.524, P<0.001, and 69.0% (K = 0.49, P<0.001 agreement between graders for FAF abnormality patterns. Patients with AMD were at greater risk for peripheral FAF abnormalities (OR: 3.43, P = 0.019 and patients with FAF abnormalities on central macular ResMax images were at greater risk of peripheral FAF findings (OR: 5.19, P = 0.017.Subjective interpretation of FAF images has moderate reproducibility and validity in assessment of peripheral FAF abnormalities. Peripheral FAF abnormalities are seen in both AMD and control patients. Those with AMD, poor visual acuity, and macular FAF abnormalities are at greater risk.

The Relative Importance of Low Significance Level and High Power in Multiple Tests of Significance.

Science.gov (United States)

Westermann, Rainer; Hager, Willi

1983-01-01

Two psychological experiments--Anderson and Shanteau (1970), Berkowitz and LePage (1967)--are reanalyzed to present the problem of the relative importance of low Type 1 error probability and high power when answering a research question by testing several statistical hypotheses. (Author/PN)

Statistical Validation of a Web-Based GIS Application and Its Applicability to Cardiovascular-Related Studies

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Jae Eun Lee

2015-12-01

Full Text Available Purpose: There is abundant evidence that neighborhood characteristics are significantly linked to the health of the inhabitants of a given space within a given time frame. This study is to statistically validate a web-based GIS application designed to support cardiovascular-related research developed by the NIH funded Research Centers in Minority Institutions (RCMI Translational Research Network (RTRN Data Coordinating Center (DCC and discuss its applicability to cardiovascular studies. Methods: Geo-referencing, geocoding and geospatial analyses were conducted for 500 randomly selected home addresses in a U.S. southeastern Metropolitan area. The correlation coefficient, factor analysis and Cronbach’s alpha (α were estimated to quantify measures of the internal consistency, reliability and construct/criterion/discriminant validity of the cardiovascular-related geospatial variables (walk score, number of hospitals, fast food restaurants, parks and sidewalks. Results: Cronbach’s α for CVD GEOSPATIAL variables was 95.5%, implying successful internal consistency. Walk scores were significantly correlated with number of hospitals (r = 0.715; p < 0.0001, fast food restaurants (r = 0.729; p < 0.0001, parks (r = 0.773; p < 0.0001 and sidewalks (r = 0.648; p < 0.0001 within a mile from homes. It was also significantly associated with diversity index (r = 0.138, p = 0.0023, median household incomes (r = −0.181; p < 0.0001, and owner occupied rates (r = −0.440; p < 0.0001. However, its non-significant correlation was found with median age, vulnerability, unemployment rate, labor force, and population growth rate. Conclusion: Our data demonstrates that geospatial data generated by the web-based application were internally consistent and demonstrated satisfactory validity. Therefore, the GIS application may be useful to apply to cardiovascular-related studies aimed to investigate potential impact of geospatial factors on diseases and/or the long

Outpatient psychodynamic group psychotherapy - outcomes related to personality disorder, severity, age and gender.

Science.gov (United States)

Kvarstein, Elfrida Hartveit; Nordviste, Ola; Dragland, Lone; Wilberg, Theresa

2017-02-01

Outpatient group psychotherapy is frequent within specialist services, recruits a mixed population, but effects are poorly documented. This study investigates long-term outcomes for patients with personality disorder (PD) treated in outpatient, psychodynamic groups within secondary mental health service. A naturalistic study (N = 103) with repeated assessments of process and clinical outcomes. Longitudinal statistics are linear mixed models. The main PDs were avoidant, borderline and NOS PD, mean number of PDs 1.4(SD0.7), 60% females and mean initial age 38(SD10) years. Mean treatment duration was 1.5(SD 0.9) years. Therapist alliance and experienced group climate was satisfactory and stable. Improvements were significant (symptom distress, interpersonal problems, occupational functioning and additional mental health services), irrespective of general PD-severity, but not of PD-type, age or gender. The study demonstrates PD NOS benefits across all outcomes, occupational improvements for avoidant PD, despite prevailing symptoms, but generally poorer outcomes for males and age >38 years. For borderline PD, experienced conflict was stronger, treatment duration shorter and outcomes poor for early drop-outs (28%). Psychodynamic group psychotherapy is a recommendable treatment for moderate PDs, which may address avoidant strategies, but may not meet clinical challenges of borderline PD. The outcome differences related to gender and age are noteworthy. Copyright © 2016 John Wiley & Sons, Ltd. Copyright © 2016 John Wiley & Sons, Ltd.

Recent Literature on Whether Statistical Significance Tests Should or Should Not Be Banned.

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Deegear, James

This paper summarizes the literature regarding statistical significant testing with an emphasis on recent literature in various discipline and literature exploring why researchers have demonstrably failed to be influenced by the American Psychological Association publication manual's encouragement to report effect sizes. Also considered are…

Age-related practice effects across longitudinal neuropsychological assessments in older people with schizophrenia.

Science.gov (United States)

Granholm, Eric; Link, Peter; Fish, Scott; Kraemer, Helena; Jeste, Dilip

2010-09-01

The relationship between aging and practice effects on longitudinal neuropsychological assessments was investigated in middle-aged and older people with schizophrenia and healthy controls. Older people with schizophrenia (n = 107; M age = 56.1) and age-comparable nonpsychiatric controls (n = 107; M age = 57.7) were scheduled to receive annual assessments on a comprehensive battery of neuropsychological tests for an average of 2.5 years (range 11 months to 4 years). Mixed-model analyses were used to separately examine the effects of practice and age on test performance. Number of prior assessments (practice) was associated with significant performance improvement across assessments, whereas older age was associated with significant decline in performance. The groups did not differ significantly in extent of age-related cognitive decline, but a three-way interaction among group, age, and practice was found, such that greater age-related decline in practice effects were found for older people with schizophrenia relative to nonpsychiatric participants. This study did not find any evidence of neurodegenerative age-related decline in neuropsychological abilities in middle-aged and older people with schizophrenia, but older age was associated with diminished ability to benefit from repeated exposure to cognitive tasks in people with schizophrenia. Cognitive impairment in schizophrenia may combine with cognitive decline associated with normal aging to reduce practice effects in older patients. These findings have important implications for the design of studies examining the longitudinal trajectory of cognitive functioning across the life span of people with schizophrenia, as well as clinical trials that attempt to demonstrate cognitive enhancement in these individuals. Copyright 2010 APA, all rights reserved.

Cross-population validation of statistical distance as a measure of physiological dysregulation during aging.

Science.gov (United States)

Cohen, Alan A; Milot, Emmanuel; Li, Qing; Legault, Véronique; Fried, Linda P; Ferrucci, Luigi

2014-09-01

Measuring physiological dysregulation during aging could be a key tool both to understand underlying aging mechanisms and to predict clinical outcomes in patients. However, most existing indices are either circular or hard to interpret biologically. Recently, we showed that statistical distance of 14 common blood biomarkers (a measure of how strange an individual's biomarker profile is) was associated with age and mortality in the WHAS II data set, validating its use as a measure of physiological dysregulation. Here, we extend the analyses to other data sets (WHAS I and InCHIANTI) to assess the stability of the measure across populations. We found that the statistical criteria used to determine the original 14 biomarkers produced diverging results across populations; in other words, had we started with a different data set, we would have chosen a different set of markers. Nonetheless, the same 14 markers (or the subset of 12 available for InCHIANTI) produced highly similar predictions of age and mortality. We include analyses of all combinatorial subsets of the markers and show that results do not depend much on biomarker choice or data set, but that more markers produce a stronger signal. We conclude that statistical distance as a measure of physiological dysregulation is stable across populations in Europe and North America. Copyright © 2014 Elsevier Inc. All rights reserved.

Reduced age-related degeneration of the hippocampal subiculum in long-term meditators.

Science.gov (United States)

Kurth, Florian; Cherbuin, Nicolas; Luders, Eileen

2015-06-30

Normal aging is known to result in a reduction of gray matter within the hippocampal complex, particularly in the subiculum. The present study was designed to address the question whether the practice of meditation can amend this age-related subicular atrophy. For this purpose, we established the correlations between subicular volume and chronological age within 50 long-term meditators and 50 control subjects. High-resolution magnetic resonance imaging (MRI) scans were automatically processed combining cytoarchitectonically defined probabilistic maps with advanced tissue segmentation and registration methods. Overall, we observed steeper negative regression slopes in controls. The analysis further revealed a significant group-by-age interaction for the left subiculum with a significant negative correlation between age and subicular volume in controls, but no significant correlation in meditators. Altogether, these findings seem to suggest a reduced age-related atrophy of the left subiculum in meditators compared to healthy controls. Possible explanations might be a relative increase of subicular tissue over time through long-term training as meditation is a process that incorporates regular and ongoing mental efforts. Alternatively, because meditation is an established form of reducing stress, our observation might reflect an overall preservation of subicular tissue through a reduced neuronal vulnerability to negative effects of stress. Copyright © 2015 Elsevier Ireland Ltd. All rights reserved.

Age-related aspects of addiction

OpenAIRE

Koechl, Birgit; Unger, Annemarie; Fischer, Gabriele

2012-01-01

Research has shown that substance use, abuse and addiction are not limited to a specific age group. Problems related to substance addiction are an important cause of morbidity in the population aged 65 and above, especially the abuse of prescription drugs and legal substances. A lack of evidence-based studies and tailored treatment options for the aging population is evident. Appropriate and effective health-care is an important goal to improve health-related quality of life of elderly people...

Safety significance of component ageing, exemplary for MOV, based on French and German operating experience

Energy Technology Data Exchange (ETDEWEB)

Morlent, O. [CEA Fontenay-aux-Roses, 92 (France). Inst. de Protection et de Surete Nucleaire; Michel, F. [Gesellschaft fuer Anlagen- und Reaktorsicherheit (GRS) mbH, Garching (Germany)

2001-07-01

An outline is given of how IPSN and GRS assess the effects of physical ageing on the safety of French and German Nuclear Power Plants (NPPs) on the basis of the available knowledge and how investigations are carried out. The presentation is focused exemplary on a preliminary study illustrating approaches for the evaluation of the ageing behaviour of active components, the motor-operated valves (MOV). The results so far seems to demonstrate that the developed methodological approaches are suitable to obtain qualitative evidence with regard to the ageing behaviour of technical facilities such as MOV. The evaluation of the operating experience with French 900 MWe plants seems to reveal, for MOV of one system, a trend similar to some international findings about ageing-related events with increasing operating time; this trend will have to be confirmed. For the German NPPs so far, there appears to be no significant increase of ageing-related events concerning MOV as the plants get older. Future work on ageing scheduled at IPSN and GRS includes further cooperation on this issue, too; a deep analysis is necessary to explain the reasons of such apparent differences before any conclusion. (authors)

Safety significance of component ageing, exemplary for MOV, based on French and German operating experience

International Nuclear Information System (INIS)

Morlent, O.

2001-01-01

An outline is given of how IPSN and GRS assess the effects of physical ageing on the safety of French and German Nuclear Power Plants (NPPs) on the basis of the available knowledge and how investigations are carried out. The presentation is focused exemplary on a preliminary study illustrating approaches for the evaluation of the ageing behaviour of active components, the motor-operated valves (MOV). The results so far seems to demonstrate that the developed methodological approaches are suitable to obtain qualitative evidence with regard to the ageing behaviour of technical facilities such as MOV. The evaluation of the operating experience with French 900 MWe plants seems to reveal, for MOV of one system, a trend similar to some international findings about ageing-related events with increasing operating time; this trend will have to be confirmed. For the German NPPs so far, there appears to be no significant increase of ageing-related events concerning MOV as the plants get older. Future work on ageing scheduled at IPSN and GRS includes further cooperation on this issue, too; a deep analysis is necessary to explain the reasons of such apparent differences before any conclusion. (authors)

The changes of cerebral morphology related to aging in Taiwanese population.

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Hsiao-Lan Sharon Wang

Full Text Available A cross-sectional study with the 3-dimensional (3D MRI reconstruction technique was conducted to investigate cerebral complexity changes related to age differences in native Taiwanese population. In our sample of 85 participants aged between 25 and 81, age was associated with gradual ventricular expansion. A nonlinear quadratic relationship between white matter volume and age was found overall in the brain. Widespread age-related reduction in white matter was detected from late adulthood onwards. However, no significant age-related changes in the cortex and whole brain volume were determined throughout adulthood. These findings provided information in describing brain structural complexity, which might in the future serve as an objective diagnostic index or as a predictive parameter for neurological diseases. Our method then may be used for cross-cultural longitudinal studies to evaluate the effect of disease, environment and aging on the brain.

Age-Related White Matter Changes

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Yun Yun Xiong

2011-01-01

Full Text Available Age-related white matter changes (WMC are considered manifestation of arteriolosclerotic small vessel disease and are related to age and vascular risk factors. Most recent studies have shown that WMC are associated with a host of poor outcomes, including cognitive impairment, dementia, urinary incontinence, gait disturbances, depression, and increased risk of stroke and death. Although the clinical relevance of WMC has been extensively studied, to date, only very few clinical trials have evaluated potential symptomatic or preventive treatments for WMC. In this paper, we reviewed the current understanding in the pathophysiology, epidemiology, clinical importance, chemical biomarkers, and treatments of age-related WMC.

Hippocampal CA1 transcriptional profile of sleep deprivation: relation to aging and stress.

Directory of Open Access Journals (Sweden)

Nada M Porter

Full Text Available Many aging changes seem similar to those elicited by sleep-deprivation and psychosocial stress. Further, sleep architecture changes with age suggest an age-related loss of sleep. Here, we hypothesized that sleep deprivation in young subjects would elicit both stress and aging-like transcriptional responses.F344 rats were divided into control and sleep deprivation groups. Body weight, adrenal weight, corticosterone level and hippocampal CA1 transcriptional profiles were measured. A second group of animals was exposed to novel environment stress (NES, and their hippocampal transcriptional profiles measured. A third cohort exposed to control or SD was used to validate transcriptional results with Western blots. Microarray results were statistically contrasted with prior transcriptional studies. Microarray results pointed to sleep pressure signaling and macromolecular synthesis disruptions in the hippocampal CA1 region. Animals exposed to NES recapitulated nearly one third of the SD transcriptional profile. However, the SD-aging relationship was more complex. Compared to aging, SD profiles influenced a significant subset of genes. mRNA associated with neurogenesis and energy pathways showed agreement between aging and SD, while immune, glial, and macromolecular synthesis pathways showed SD profiles that opposed those seen in aging.We conclude that although NES and SD exert similar transcriptional changes, selective presynaptic release machinery and Homer1 expression changes are seen in SD. Among other changes, the marked decrease in Homer1 expression with age may represent an important divergence between young and aged brain response to SD. Based on this, it seems reasonable to conclude that therapeutic strategies designed to promote sleep in young subjects may have off-target effects in the aged. Finally, this work identifies presynaptic vesicular release and intercellular adhesion molecular signatures as novel therapeutic targets to counter

Age-related increase in brain activity during task-related and -negative networks and numerical inductive reasoning.

Science.gov (United States)

Sun, Li; Liang, Peipeng; Jia, Xiuqin; Qi, Zhigang; Li, Kuncheng

2014-01-01

Recent neuroimaging studies have shown that elderly adults exhibit increased and decreased activation on various cognitive tasks, yet little is known about age-related changes in inductive reasoning. To investigate the neural basis for the aging effect on inductive reasoning, 15 young and 15 elderly subjects performed numerical inductive reasoning while in a magnetic resonance (MR) scanner. Functional magnetic resonance imaging (fMRI) analysis revealed that numerical inductive reasoning, relative to rest, yielded multiple frontal, temporal, parietal, and some subcortical area activations for both age groups. In addition, the younger participants showed significant regions of task-induced deactivation, while no deactivation occurred in the elderly adults. Direct group comparisons showed that elderly adults exhibited greater activity in regions of task-related activation and areas showing task-induced deactivation (TID) in the younger group. Our findings suggest an age-related deficiency in neural function and resource allocation during inductive reasoning.

A novel multi-tissue RNA diagnostic of healthy ageing relates to cognitive health status.

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Sood, Sanjana; Gallagher, Iain J; Lunnon, Katie; Rullman, Eric; Keohane, Aoife; Crossland, Hannah; Phillips, Bethan E; Cederholm, Tommy; Jensen, Thomas; van Loon, Luc J C; Lannfelt, Lars; Kraus, William E; Atherton, Philip J; Howard, Robert; Gustafsson, Thomas; Hodges, Angela; Timmons, James A

2015-09-07

Diagnostics of the human ageing process may help predict future healthcare needs or guide preventative measures for tackling diseases of older age. We take a transcriptomics approach to build the first reproducible multi-tissue RNA expression signature by gene-chip profiling tissue from sedentary normal subjects who reached 65 years of age in good health. One hundred and fifty probe-sets form an accurate classifier of young versus older muscle tissue and this healthy ageing RNA classifier performed consistently in independent cohorts of human muscle, skin and brain tissue (n = 594, AUC = 0.83-0.96) and thus represents a biomarker for biological age. Using the Uppsala Longitudinal Study of Adult Men birth-cohort (n = 108) we demonstrate that the RNA classifier is insensitive to confounding lifestyle biomarkers, while greater gene score at age 70 years is independently associated with better renal function at age 82 years and longevity. The gene score is 'up-regulated' in healthy human hippocampus with age, and when applied to blood RNA profiles from two large independent age-matched dementia case-control data sets (n = 717) the healthy controls have significantly greater gene scores than those with cognitive impairment. Alone, or when combined with our previously described prototype Alzheimer disease (AD) RNA 'disease signature', the healthy ageing RNA classifier is diagnostic for AD. We identify a novel and statistically robust multi-tissue RNA signature of human healthy ageing that can act as a diagnostic of future health, using only a peripheral blood sample. This RNA signature has great potential to assist research aimed at finding treatments for and/or management of AD and other ageing-related conditions.

The age-related performance decline in ultraendurance mountain biking.

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Haupt, Samuel; Knechtle, Beat; Knechtle, Patrizia; Rüst, Christoph Alexander; Rosemann, Thomas; Lepers, Romuald

2013-01-01

The age-related changes in ultraendurance performance have been previously examined for running and triathlon but not mountain biking. The aims of this study were (i) to describe the performance trends and (ii) to analyze the age-related performance decline in ultraendurance mountain biking in a 120-km ultraendurance mountain bike race the "Swiss Bike Masters" from 1995 to 2009 in 9,325 male athletes. The mean (±SD) race time decreased from 590 ± 80 min to 529 ± 88 min for overall finishers and from 415 ± 8 min to 359 ± 16 min for the top 10 finishers, respectively. The mean (±SD) age of all finishers significantly (P Bike Masters" appears to start earlier compared with other ultraendurance sports.

Towards an explanation of age-related difficulties in crossing a two-way street.

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Dommes, Aurélie; Lay, Tristan Le; Vienne, Fabrice; Dang, Nguyen-Thong; Beaudoin, Alexandra Perrot; Do, Manh Cuong

2015-12-01

Crossing a two-way street is a complex task that involves visual, cognitive and motor abilities, all of which are known to decline with ageing. In particular, older pedestrians may experience difficulties when crossing two-way streets because of incorrect gap acceptance choices and impossible or unperceived evasive actions. To understand the overrepresentation of older pedestrians in crash statistics, several experimental studies have sought to identify traffic-related factors as well as those related to the abilities of the individuals themselves. However, none of these studies has required participants to actually walk across an experimental two-way street with curbs, which is a particularly challenging situation for older pedestrians. To fill this research gap, a quasi-experiment was conducted in a simulator including a total of 58 healthy aged participants (25 younger-old [age 60-72] and 33 older-old [age 72-92]) and 25 young adults (aged 18-25 years). Participants carried out a street-crossing task in a simulated two-way traffic environment; curbs were present on both sides of the experimental street. Participants also undertook a battery of tests to assess their visual and cognitive abilities. In addition, during the experiment, the participants' gait parameters were recorded. In line with earlier findings, the older-old group of participants made a higher number of decisions that led to collisions with approaching cars compared with the other groups. The two groups of older participants experienced specific difficulties when vehicles were in the far lane or when they approached rapidly. A regression analysis identified visual acuity, speed of processing (assessed using the UFOV(®) test), and step length as significant predictors of collisions. Our results have implications for understanding the difficulties experienced by older pedestrians and allow to draw up several recommendations for improving their safety. Copyright © 2015 Elsevier Ltd. All rights

Bayesian estimation of isotopic age differences

International Nuclear Information System (INIS)

Curl, R.L.

1988-01-01

Isotopic dating is subject to uncertainties arising from counting statistics and experimental errors. These uncertainties are additive when an isotopic age difference is calculated. If large, they can lead to no significant age difference by classical statistics. In many cases, relative ages are known because of stratigraphic order or other clues. Such information can be used to establish a Bayes estimate of age difference which will include prior knowledge of age order. Age measurement errors are assumed to be log-normal and a noninformative but constrained bivariate prior for two true ages in known order is adopted. True-age ratio is distributed as a truncated log-normal variate. Its expected value gives an age-ratio estimate, and its variance provides credible intervals. Bayesian estimates of ages are different and in correct order even if measured ages are identical or reversed in order. For example, age measurements on two samples might both yield 100 ka with coefficients of variation of 0.2. Bayesian estimates are 22.7 ka for age difference with a 75% credible interval of [4.4, 43.7] ka

Fatty old hearts: role of cardiac lipotoxicity in age-related cardiomyopathy

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Konstantinos Drosatos

2016-08-01

Full Text Available Age-related cardiomyopathy accounts for a significant part of heart failure cases. Imbalance of the energetic equilibrium of the heart along with mitochondrial dysfunction and impaired β-adrenergic receptor signaling contributes in the aggravation of cardiac function in the elderly. In this review article, studies that correlate cardiac aging with lipotoxicity are summarized. The involvement of inhibition of peroxisome proliferator-activated receptor-α, β-adrenergic receptor desensitization, and mitochondrial dysfunction as underlying mechanisms for the lipid-driven age-related cardiomyopathy are presented with the aim to indicate potential therapeutic targets for cardiac aging.

A Computational Tool for Testing Dose-related Trend Using an Age-adjusted Bootstrap-based Poly-k Test

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Hojin Moon

2006-08-01

Full Text Available A computational tool for testing for a dose-related trend and/or a pairwise difference in the incidence of an occult tumor via an age-adjusted bootstrap-based poly-k test and the original poly-k test is presented in this paper. The poly-k test (Bailer and Portier 1988 is a survival-adjusted Cochran-Armitage test, which achieves robustness to effects of differential mortality across dose groups. The original poly-k test is asymptotically standard normal under the null hypothesis. However, the asymptotic normality is not valid if there is a deviation from the tumor onset distribution that is assumed in this test. Our age-adjusted bootstrap-based poly-k test assesses the significance of assumed asymptotic normal tests and investigates an empirical distribution of the original poly-k test statistic using an age-adjusted bootstrap method. A tumor of interest is an occult tumor for which the time to onset is not directly observable. Since most of the animal carcinogenicity studies are designed with a single terminal sacrifice, the present tool is applicable to rodent tumorigenicity assays that have a single terminal sacrifice. The present tool takes input information simply from a user screen and reports testing results back to the screen through a user-interface. The computational tool is implemented in C/C++ and is applied to analyze a real data set as an example. Our tool enables the FDA and the pharmaceutical industry to implement a statistical analysis of tumorigenicity data from animal bioassays via our age-adjusted bootstrap-based poly-k test and the original poly-k test which has been adopted by the National Toxicology Program as its standard statistical test.

Childhood-compared to adolescent-onset bipolar disorder has more statistically significant clinical correlates.

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Holtzman, Jessica N; Miller, Shefali; Hooshmand, Farnaz; Wang, Po W; Chang, Kiki D; Hill, Shelley J; Rasgon, Natalie L; Ketter, Terence A

2015-07-01

The strengths and limitations of considering childhood-and adolescent-onset bipolar disorder (BD) separately versus together remain to be established. We assessed this issue. BD patients referred to the Stanford Bipolar Disorder Clinic during 2000-2011 were assessed with the Systematic Treatment Enhancement Program for BD Affective Disorders Evaluation. Patients with childhood- and adolescent-onset were compared to those with adult-onset for 7 unfavorable bipolar illness characteristics with replicated associations with early-onset patients. Among 502 BD outpatients, those with childhood- (adolescent- (13-18 years, N=218) onset had significantly higher rates for 4/7 unfavorable illness characteristics, including lifetime comorbid anxiety disorder, at least ten lifetime mood episodes, lifetime alcohol use disorder, and prior suicide attempt, than those with adult-onset (>18 years, N=174). Childhood- but not adolescent-onset BD patients also had significantly higher rates of first-degree relative with mood disorder, lifetime substance use disorder, and rapid cycling in the prior year. Patients with pooled childhood/adolescent - compared to adult-onset had significantly higher rates for 5/7 of these unfavorable illness characteristics, while patients with childhood- compared to adolescent-onset had significantly higher rates for 4/7 of these unfavorable illness characteristics. Caucasian, insured, suburban, low substance abuse, American specialty clinic-referred sample limits generalizability. Onset age is based on retrospective recall. Childhood- compared to adolescent-onset BD was more robustly related to unfavorable bipolar illness characteristics, so pooling these groups attenuated such relationships. Further study is warranted to determine the extent to which adolescent-onset BD represents an intermediate phenotype between childhood- and adult-onset BD. Copyright © 2015 Elsevier B.V. All rights reserved.

Bridging Weighted Rules and Graph Random Walks for Statistical Relational Models

Directory of Open Access Journals (Sweden)

Seyed Mehran Kazemi

2018-02-01

Full Text Available The aim of statistical relational learning is to learn statistical models from relational or graph-structured data. Three main statistical relational learning paradigms include weighted rule learning, random walks on graphs, and tensor factorization. These paradigms have been mostly developed and studied in isolation for many years, with few works attempting at understanding the relationship among them or combining them. In this article, we study the relationship between the path ranking algorithm (PRA, one of the most well-known relational learning methods in the graph random walk paradigm, and relational logistic regression (RLR, one of the recent developments in weighted rule learning. We provide a simple way to normalize relations and prove that relational logistic regression using normalized relations generalizes the path ranking algorithm. This result provides a better understanding of relational learning, especially for the weighted rule learning and graph random walk paradigms. It opens up the possibility of using the more flexible RLR rules within PRA models and even generalizing both by including normalized and unnormalized relations in the same model.

Serum 25-hydroxyvitamin D and Age-Related Cataract.

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Park, Sangshin; Choi, Nam-Kyong

2017-10-01

Cataract and insufficient vitamin D intake are both increasing worldwide concerns, yet little is known about the relationship between serum 25-hydroxyvitamin D (25(OH)D) levels and age-related cataract. We performed this study to determine the association between serum 25(OH)D levels and age-related cataract in adults. Study participants comprised 16,086 adults aged 40 years or older who had never been diagnosed with or undergone surgery for cataract using Korean National Health and Nutrition Examination Survey data from 2008 to 2012. Participants were assessed to have cataract when diagnosed with cortical, nuclear, anterior subcapsular, posterior subcapsular, or mixed cataract. Odds ratios (ORs) and 95% confidence intervals (CIs) were used to evaluate the magnitude and significance of the association between serum 25(OH)D levels and cataract in multivariable logistic regression models. The OR for nuclear cataract with the highest quintile of serum 25(OH)D levels was 0.86 (95% CI 0.75-0.99) compared to the lowest quintile. A linear trend across quintiles was significant. Natural log-transformed serum 25(OH)D levels were also significantly associated with nuclear cataract (OR 0.84, 95% CI 0.75-0.95). The opulation-attributable fraction of nuclear cataract due to serum 25(OH)D insufficiency (D levels were inversely associated with the risk of nuclear cataract. Prospective studies investigating the effects of serum 25(OH)D levels on the development of nuclear cataract are needed to confirm our findings.

Influence of physical fitness parameters on relative age effect on ...

African Journals Online (AJOL)

At the onset of puberty, boys experience great changes in growth and development. As such, boys who differ in age even by less than 12 months display significant differences in size, strength, power and skill levels and is known as Relative Age Effect (RAE). This study attempted to determine the prevalence of RAE in ...

Dysthymic disorder: clinical characteristics in relation to age at onset.

Science.gov (United States)

Barzega, G; Maina, G; Venturello, S; Bogetto, F

2001-09-01

The variability in the clinical presentation of dysthymia has given rise to a rich debate in literature, and various hypotheses have been proposed. One is that the clinical presentation differs in relation to age at onset. The aim of the study was to evaluate differences in socio-demographic and clinical characteristics in a sample of patients with dysthymia (DSM-IV), in relation to age at onset. 84 consecutive outpatients with a diagnosis of dysthymia (DSM-IV) were studied. All subjects were evaluated by a semistructured clinical interview and the following rating scales: HAM-A, HAM-D, MADRS, Paykel's Interview for Recent Life Events. 23.8% of the sample had early-onset (dysthymia. Patients with early-onset disorder were significantly younger at the observation, more frequently female and single. They had a significantly longer duration of illness and in a significantly higher percentage had already received a specialist treatment before admission in the present trial. No differences in the frequency of symptoms were observed. A significantly higher percentage of patients with late-onset disease reported at least one stressful event in the year preceding the onset of dysthymia. A positive history of major depression was significantly more common among the early-onset group; social phobia, panic disorder and conversive disorder were also more frequent in this group. The late-onset patients frequently presented generalized anxiety disorder, substance abuse and somatization disorder. The study is retrospective and enrolls a limited number of cases. The present study agrees with other reports on the differences in clinical presentation of dysthymia according to age at onset. Although they are not actually related to age at onset, some interesting findings emerged in the symptomatological characterization of the disorder, referring to the diagnostic criteria proposed in DSM-IV.

Age Related Changes in Hematological Values of Myanmar Local Puppies

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Thandar Oo

2017-10-01

Full Text Available The hematological parameters were used to monitor the health status and its components also changed according to the ages. However, there were no reports for this issues in Myanmar local dogs. Thus, this study was carried out to investigate the age-related changes on the hematological parameters of local puppies in Myanmar. Ten local puppies with the age of 2-3 month old were used in this experiment, which was lasted for 8 weeks.The daily clinical examinations were conducted throughout the entire experimental period for general health check-up. Haematological parameters (Total WBC count and its differential counts, and RBC, HCT, MCV, HGB, MCH, MCHC and platelets were measured bi-weekly with Abacus Vet-5 automate haematology analyser. According to the results, the total WBC and eosinophil counts were not significantly different (P>0.05, while lymphocytes, monocytes, neutrophils and basophils were significantly different (P0.05 throughout the experimental periods. Thus, the age-related changes were observed on cell counts of lymphocytes, monocytes, neutrophils, basophils in Myanmar local puppies.

Statistics and Corporate Environmental Management: Relations and Problems

DEFF Research Database (Denmark)

Madsen, Henning; Ulhøi, John Parm

1997-01-01

Statistical methods have long been used to analyse the macroeconomic consequences of environmentally damaging activities, political actions to control, prevent, or reduce these damages, and environmental problems in the natural environment. Up to now, however, they have had a limited and not very...... specific use in corporate environmental management systems. This paper will address some of the special problems related to the use of statistical techniques in corporate environmental management systems. One important aspect of this is the interaction of internal decisions and activities with conditions...

Splicing regulatory factors, ageing and age-related disease.

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Latorre, Eva; Harries, Lorna W

2017-07-01

Alternative splicing is a co-transcriptional process, which allows for the production of multiple transcripts from a single gene and is emerging as an important control point for gene expression. Alternatively expressed isoforms often have antagonistic function and differential temporal or spatial expression patterns, yielding enormous plasticity and adaptability to cells and increasing their ability to respond to environmental challenge. The regulation of alternative splicing is critical for numerous cellular functions in both pathological and physiological conditions, and deregulated alternative splicing is a key feature of common chronic diseases. Isoform choice is controlled by a battery of splicing regulatory proteins, which include the serine arginine rich (SRSF) proteins and the heterogeneous ribonucleoprotein (hnRNP) classes of genes. These important splicing regulators have been implicated in age-related disease, and in the ageing process itself. This review will outline the important contribution of splicing regulator proteins to ageing and age-related disease. Copyright © 2017 Elsevier B.V. All rights reserved.

The distribution of P-values in medical research articles suggested selective reporting associated with statistical significance.

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Perneger, Thomas V; Combescure, Christophe

2017-07-01

Published P-values provide a window into the global enterprise of medical research. The aim of this study was to use the distribution of published P-values to estimate the relative frequencies of null and alternative hypotheses and to seek irregularities suggestive of publication bias. This cross-sectional study included P-values published in 120 medical research articles in 2016 (30 each from the BMJ, JAMA, Lancet, and New England Journal of Medicine). The observed distribution of P-values was compared with expected distributions under the null hypothesis (i.e., uniform between 0 and 1) and the alternative hypothesis (strictly decreasing from 0 to 1). P-values were categorized according to conventional levels of statistical significance and in one-percent intervals. Among 4,158 recorded P-values, 26.1% were highly significant (P values values equal to 1, and (3) about twice as many P-values less than 0.05 compared with those more than 0.05. The latter finding was seen in both randomized trials and observational studies, and in most types of analyses, excepting heterogeneity tests and interaction tests. Under plausible assumptions, we estimate that about half of the tested hypotheses were null and the other half were alternative. This analysis suggests that statistical tests published in medical journals are not a random sample of null and alternative hypotheses but that selective reporting is prevalent. In particular, significant results are about twice as likely to be reported as nonsignificant results. Copyright © 2017 Elsevier Inc. All rights reserved.

Cystic Lesions in the Greater Tuberosity of the Humerus: The Relation to Rotator Cuff Tears and Age

Energy Technology Data Exchange (ETDEWEB)

Kim, Gang Deuk; Oh, Jung Taek [Wonkwang University Hospital, Iksan (Korea, Republic of)

2008-12-15

This study was designed to investigate the location of cystic lesions in the greater tuberosity of the humerus and the relationship to rotator cuff tears and age. A total of 78 patients (age range, 19-82 years; mean age, 51 years) who underwent arthroscopy or open surgery after MR arthrography (MRA) for a painful shoulder were enrolled in the study. The location of the cystic lesions were classified as 'A' for a supraspinatus insertion site, as 'C' for an infraspinatus insertion site, as 'B' for both a supraspinatus and infraspinatus insertion site, as 'BG' for a site posterior to the bicipital groove and as 'P' for a site at the bare area of the humeral head. The location of cystic lesions and supraspinatus and infraspinatus tears were evaluated on MRA. Statistical analyses used the chi-squared test and logistic regression. 'BG' and 'A' cystic lesions were related to the presence of a supraspinatus tear, 'C' cystic lesions were related to the presence of an infraspinatus tear and 'B' cystic lesions were related to the presence of both supraspinatus and infraspinatus tears (p < 0.05). 'P' cystic lesions were not related to the presence of rotator cuff tears. The incidence of cystic lesions increased with age, but with no statistical correlation. Cystic lesions at the supraspinatus and infraspinatus insertion sites are useful to predict the presence of a rotator cuff tear, but cystic lesions were not age related

Cloud-based solution to identify statistically significant MS peaks differentiating sample categories.

Science.gov (United States)

Ji, Jun; Ling, Jeffrey; Jiang, Helen; Wen, Qiaojun; Whitin, John C; Tian, Lu; Cohen, Harvey J; Ling, Xuefeng B

2013-03-23

Mass spectrometry (MS) has evolved to become the primary high throughput tool for proteomics based biomarker discovery. Until now, multiple challenges in protein MS data analysis remain: large-scale and complex data set management; MS peak identification, indexing; and high dimensional peak differential analysis with the concurrent statistical tests based false discovery rate (FDR). "Turnkey" solutions are needed for biomarker investigations to rapidly process MS data sets to identify statistically significant peaks for subsequent validation. Here we present an efficient and effective solution, which provides experimental biologists easy access to "cloud" computing capabilities to analyze MS data. The web portal can be accessed at http://transmed.stanford.edu/ssa/. Presented web application supplies large scale MS data online uploading and analysis with a simple user interface. This bioinformatic tool will facilitate the discovery of the potential protein biomarkers using MS.

Improved statistical power with a sparse shape model in detecting an aging effect in the hippocampus and amygdala

Science.gov (United States)

Chung, Moo K.; Kim, Seung-Goo; Schaefer, Stacey M.; van Reekum, Carien M.; Peschke-Schmitz, Lara; Sutterer, Matthew J.; Davidson, Richard J.

2014-03-01

The sparse regression framework has been widely used in medical image processing and analysis. However, it has been rarely used in anatomical studies. We present a sparse shape modeling framework using the Laplace- Beltrami (LB) eigenfunctions of the underlying shape and show its improvement of statistical power. Tradition- ally, the LB-eigenfunctions are used as a basis for intrinsically representing surface shapes as a form of Fourier descriptors. To reduce high frequency noise, only the first few terms are used in the expansion and higher frequency terms are simply thrown away. However, some lower frequency terms may not necessarily contribute significantly in reconstructing the surfaces. Motivated by this idea, we present a LB-based method to filter out only the significant eigenfunctions by imposing a sparse penalty. For dense anatomical data such as deformation fields on a surface mesh, the sparse regression behaves like a smoothing process, which will reduce the error of incorrectly detecting false negatives. Hence the statistical power improves. The sparse shape model is then applied in investigating the influence of age on amygdala and hippocampus shapes in the normal population. The advantage of the LB sparse framework is demonstrated by showing the increased statistical power.

Prevalence of age-related maculopathy and age-related macular degeneration among the inuit in Greenland. The Greenland Inuit Eye Study

DEFF Research Database (Denmark)

Andersen, Mads Varis Nis; Rosenberg, Thomas; la Cour, Morten

2008-01-01

To examine the age- and gender-specific prevalence and describe the common phenotype of early age-related maculopathy (ARM) and late-stage age-related macular degeneration (AMD) among the Inuit in Greenland.......To examine the age- and gender-specific prevalence and describe the common phenotype of early age-related maculopathy (ARM) and late-stage age-related macular degeneration (AMD) among the Inuit in Greenland....

Statistically significant dependence of the Xaa-Pro peptide bond conformation on secondary structure and amino acid sequence

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Leitner Dietmar

2005-04-01

Full Text Available Abstract Background A reliable prediction of the Xaa-Pro peptide bond conformation would be a useful tool for many protein structure calculation methods. We have analyzed the Protein Data Bank and show that the combined use of sequential and structural information has a predictive value for the assessment of the cis versus trans peptide bond conformation of Xaa-Pro within proteins. For the analysis of the data sets different statistical methods such as the calculation of the Chou-Fasman parameters and occurrence matrices were used. Furthermore we analyzed the relationship between the relative solvent accessibility and the relative occurrence of prolines in the cis and in the trans conformation. Results One of the main results of the statistical investigations is the ranking of the secondary structure and sequence information with respect to the prediction of the Xaa-Pro peptide bond conformation. We observed a significant impact of secondary structure information on the occurrence of the Xaa-Pro peptide bond conformation, while the sequence information of amino acids neighboring proline is of little predictive value for the conformation of this bond. Conclusion In this work, we present an extensive analysis of the occurrence of the cis and trans proline conformation in proteins. Based on the data set, we derived patterns and rules for a possible prediction of the proline conformation. Upon adoption of the Chou-Fasman parameters, we are able to derive statistically relevant correlations between the secondary structure of amino acid fragments and the Xaa-Pro peptide bond conformation.

Recent developments in the management of dry age-related macular degeneration

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Buschini E

2015-04-01

Full Text Available Elisa Buschini, Antonio M Fea, Carlo A Lavia, Marco Nassisi, Giulia Pignata, Marta Zola, Federico M Grignolo Ospedale Oftalmico, Ophthalmic Section, Department of Clinical Pathophysiology, University of Turin, Turin, Italy Abstract: Dry age-related macular degeneration (AMD, also called geographic atrophy, is characterized by the atrophy of outer retinal layers and retinal pigment epithelium (RPE cells. Dry AMD accounts for 80% of all intermediate and advanced forms of the disease. Although vision loss is mainly due to the neovascular form (75%, dry AMD remains a challenge for ophthalmologists because of the lack of effective therapies. Actual management consists of lifestyle modification, vitamin supplements, and supportive measures in the advanced stages. The Age-Related Eye Disease Study demonstrated a statistically significant protective effect of dietary supplementation of antioxidants (vitamin C, vitamin E, beta-carotene, zinc, and copper on dry AMD progression rate. It was also stated that the consumption of omega-3 polyunsaturated fatty acids, such as docosahexaenoic acid and eicosapentaenoic acid, has protective effects. Other antioxidants, vitamins, and minerals (such as crocetin, curcumin, and vitamins B9, B12, and B6 are under evaluation, but the results are still uncertain. New strategies aim to 1 reduce or block drusen formation, 2 reduce or eliminate inflammation, 3 lower the accumulation of toxic by-products from the visual cycle, 4 reduce or eliminate retinal oxidative stress, 5 improve choroidal perfusion, 6 replace/repair or regenerate lost RPE cells and photoreceptors with stem cell therapy, and 7 develop a target gene therapy. Keywords: dry AMD, geographic atrophy, new AMD therapy

Age-related changes in pre- and postmenopausal women investigated with {sup 18}F-fluoride PET - a preliminary study

Energy Technology Data Exchange (ETDEWEB)

Kurata, Seiji; Ishibashi, Masatoshi [Kurume University School of Medicine, Department of Radiology, Division of Nuclear Medicine, Kurume (Japan); Shizukuishi, Kazuya; Tateishi, Ukihide; Yoneyama, Tomohiro; Hino, Ayako; Inoue, Tomio [Yokohama City University Graduate School of Medicine, Department of Radiology, Yokohama (Japan)

2012-08-15

To evaluate the relationship between age and regional skeletal uptake at sites consisting of either predominantly trabecular or cortical bone using {sup 18}F-fluoride positron emission tomography (PET) in pre- and postmenopausal women. Thirty-two women (40.6 {+-} 12.3 years; age range 25-72 years) were assigned to one of two groups: group 1 comprised 22 premenopausal women (33 {+-} 6.5 years; age range 25-48 years) and group 2 comprised 10 postmenopausal women (56 {+-} 6.7 years; age range 49-72 years). The maximum standardized uptake value (SUVmax) was determined from the lumbar spine and the humeral shaft. Student's t-test for each unpaired dataset was used to evaluate statistical differences between the two groups. The SUVmax values for the humeral shaft and the lumbar spine were compared with aging. The SUVmax (mean {+-} SD) was 1.2 {+-} 0.5 in the humeral shaft and 4.7 {+-} 1.0 in the lumbar spine. The SUVmax in the humeral shaft correlated significantly with advancing age (r = 0.67, P < 0.01). The SUVmax in the lumbar spine declined significantly with advancing age (r = -0.50, P < 0.01). The humeral shaft of women in group 1 exhibited a significantly lower SUVmax compared to that in group 2 (1.1 {+-} 0.4 versus 1.6 {+-} 0.6; P < 0.05). On the other hand, the lumbar spine of women in group 1 exhibited a significantly higher SUVmax compared to that in group 2 (5.1 {+-} 0.7 versus 4.0 {+-} 1.1; P < 0.05). The mean SUVmax in the lumbar spine was 2.5 times greater than that in the humeral shaft in group 2. Semiquantitative analysis with {sup 18}F-fluoride PET might be a useful tool for analyzing age-related changes in pre- and postmenopausal women. (orig.)

Quantification of the relative age effect in three indices of physical performance.

Science.gov (United States)

Sandercock, Gavin R H; Taylor, Matthew J; Voss, Christine; Ogunleye, Ayodele A; Cohen, Daniel D; Parry, David A

2013-12-01

The relative age effect (RAE) describes the relationship between an individual's birth month and their level of attainment in sports. There is a clustering of birth dates just after the cutoff used for selection in age-grouped sports, and it is hypothesized that such relatively older sportspeople may enjoy maturational and physical advantages over their younger peers. There is, however, little empirical evidence of any such advantage. This study investigated whether schoolchildren's physical performance differed according to which quarter of the school year they were born in. Mass, stature, body mass index, cardiorespiratory fitness, strength, and power were measured in 10 to 16 year olds (n = 8,550, 53% male). We expressed test performance as age- and sex-specific z-scores based on reference data with age rounded down to the nearest whole year and also as units normalized for body mass. We then compared these values between yearly birth quarters. There were no significant main effects for differences in anthropometric measures in either sex. Girls born in the first quarter of the school year were significantly stronger than those born at other times when handgrip was expressed as a z-score. As z-scores, all measures were significantly higher in boys born in either the first or second yearly quarters. Relative to body mass, cardiorespiratory fitness was higher in boys born in the first quarter and power was higher in those born in the second quarter. The RAE does not appear to significantly affect girls' performance test scores when they are expressed as z-score or relative to body mass. Boys born in the first and second quarters of the year had a significant physical advantage over their relatively younger peers. These findings have practical bearing if coaches use fitness tests for talent identification and team selection. Categorizing test performance based on rounded down values of whole-year age may disadvantage children born later in the selection year. These

Radiotherapy in age-related macula degeneration

International Nuclear Information System (INIS)

Gripp, Stephan; Stammen, Johannes; Petersen, Claudia; Hartmann, Axel; Willers, Reinhart; Althaus, Christoph

2002-01-01

Purpose: To ascertain the benefit from radiotherapy in age-related macula degeneration in a single-arm longitudinal study. Methods and Materials: From 1997 to 1998, 39 patients with occult and 33 patients with classic choroidal neovascularization (CNV) were irradiated with 16 Gy. Fluorescein angiography and measurements of visual acuity were performed before and 3, 6, and 12 months after irradiation. Results: Complete follow-up data for 1 year were available from 69 patients. The mean patient age was 72 years (range 49-92). Vision decreased in 43, was stable in 18, and improved in 8 cases. The mean vision deteriorated significantly (p=0.02, Wilcoxon test), particularly within the first 3 months. Patients with occult CNV did significantly better than did those with classic CNV (p=0.03). The proportion of patients retaining vision ≥0.2 fell from 65% to 42% (p <0.01), for classic and occult CNV from 50% to 23%, and for occult CNV from 77% to 56% (p<0.02), respectively. CNV size increased in 30 patients and was stable in 38. Neither age (p=0.17) nor gender (p=0.21, chi-square test) influenced prognosis. Four patients reported transitional complaints. Conclusion: Low-dose fractionated radiotherapy with 16 Gy is well tolerated. However, vision and reading ability were not preserved in most patients

Age-related distribution of vertebral bone-marrow diffusivity

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Herrmann, Jochen, E-mail: j.herrmann@uke.de [Department of Diagnostic and Interventional Radiology, Martinistraße 52, D-20246 Hamburg (Germany); Department of Pediatric Radiology, Martinistraße 52, D-20246 Hamburg (Germany); Krstin, Nina, E-mail: ninakrstin@web.de [Department of Diagnostic and Interventional Radiology, Martinistraße 52, D-20246 Hamburg (Germany); Schoennagel, Bjoern P., E-mail: b.schoennagel@uke.de [Department of Diagnostic and Interventional Radiology, Martinistraße 52, D-20246 Hamburg (Germany); Sornsakrin, Marjike, E-mail: m.sornsakrin@uke.de [Department of Pediatrics, University Medical Center Hamburg-Eppendorf, Martinistraße 52, D-20246 Hamburg (Germany); Derlin, Thorsten, E-mail: t.derlin@uke.de [Department of Diagnostic and Interventional Radiology, Martinistraße 52, D-20246 Hamburg (Germany); Busch, Jasmin D., E-mail: jd.busch@uke.de [Department of Diagnostic and Interventional Radiology, Martinistraße 52, D-20246 Hamburg (Germany); Petersen, Kay Uwe, E-mail: Kay.Petersen@med.uni-tuebingen.de [Department of Psychiatry, University Clinic Tübingen, Calwerstraße 14 Tübingen 72076 (Germany); Graessner, Joachim, E-mail: joachim.graessner@siemens.com [Siemens AG Healthcare, Lindenplatz 2, 20099 Hamburg (Germany); Adam, Gerhard, E-mail: g.adam@uke.de [Department of Diagnostic and Interventional Radiology, Martinistraße 52, D-20246 Hamburg (Germany); Habermann, Christian R., E-mail: c.habermann@uke.de [Department of Diagnostic and Interventional Radiology, Martinistraße 52, D-20246 Hamburg (Germany)

2012-12-15

Purpose: To determine age-related diffusivity changes of the lumbar bone marrow by measurement of apparent diffusion coefficient (ADC) values. Materials and methods: The local ethics committee approved this study and written informed consent was obtained. The study group comprised 88 individuals including 75 healthy volunteers and 13 patients (48 female, 40 male; mean age 36 years, range 0–84 years). The pediatric cases were recruited from patients. Echo-planar diffusion weighted imaging (DWI) was performed with b-values of 50, 400 and 800 s/mm{sup 2}. ADC-values were calculated and measured in the 1st and 2nd vertebral body of the lumbar spine. Correlation between age and ADC-values was analyzed with Spearman's rho test. Results: The ADC values of the vertebral bone marrow of the lumbar spine showed a significant negative correlation with age (rho = −0.398, p = 0.001). The mean ADC values (×10{sup −3} mm{sup 2}/s) in the age groups 0–29 years (mean age 18.0 years, n = 42) and 30–88 years (mean age 51.6 years, n = 46) were 0.54 ± 0.07 and 0.47 ± 0.08, respectively (p < 0.001, T-test). No significant differences were found between children and young adults. Conclusion: Bone marrow ADC values of the lumbar spine show a linear decrease with growing age and thereby reflect the gradual changes of cell composition occurring during marrow conversion.

Age-related deficits in free recall: the role of rehearsal.

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Ward, Geoff; Maylor, Elizabeth A

2005-01-01

Age-related deficits have been consistently observed in free recall. Recent accounts of episodic memory suggest that these deficits could result from differential patterns of rehearsal. In the present study, 20 young and 20 older adults (mean ages 21 and 72 years, respectively) were presented with lists of 20 words for immediate free recall using the overt rehearsal methodology. The young outperformed the older adults at all serial positions. There were significant age-related differences in the patterns of overt rehearsals: Young adults rehearsed a greater number of different words than did older adults, they rehearsed words to more recent serial positions, and their rehearsals were more widely distributed throughout the list. Consistent with a recency-based account of episodic memory, age deficits in free recall are largely attributable to age differences in the recency, frequency, and distribution of rehearsals.

Age-related changes in vertebral and iliac crest 3D bone microstructure--differences and similarities.

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Thomsen, J S; Jensen, M V; Niklassen, A S; Ebbesen, E N; Brüel, A

2015-01-01

Age-related changes of vertebra and iliac crest 3D microstructure were investigated, and we showed that they were in general similar. The 95th percentile of vertebral trabecular thickness distribution increased with age for women. Surprisingly, vertebral and iliac crest bone microstructure was only weakly correlated (r = 0.38 to 0.75), despite the overall similar age-related changes. The purposes of the study were to determine the age-related changes in iliac and vertebral bone microstructure for women and men over a large age range and to investigate the relationship between the bone microstructure at these skeletal sites. Matched sets of transiliac crest bone biopsies and lumbar vertebral body (L2) specimens from 41 women (19-96 years) and 39 men (23-95 years) were micro-computed tomography (μCT) scanned, and the 3D microstructure was quantified. For both women and men, bone volume per total volume (BV/TV), connectivity density (CD), and trabecular number (Tb.N) decreased significantly, while structure model index (SMI) and trabecular separation (Tb.Sp) increased significantly with age at either skeletal site. Vertebral trabecular thickness (Tb.Th) was independent of age for both women and men, while iliac Tb.Th decreased significantly with age for men, but not for women. In general, the vertebral and iliac age-related changes were similar. The 95th percentile of the Tb.Th distribution increased significantly with age for women but was independent of age for men at the vertebral body, while it was independent of age for either sex at the iliac crest. The Tb.Th probability density functions at the two skeletal sites became significantly more similar with age for women, but not for men. The microstructural parameters at the iliac crest and the vertebral bodies were only moderately correlated from r = 0.38 for SMI in women to r = 0.75 for Tb.Sp in men. Age-related changes in vertebral and iliac bone microstructure were in general similar. The iliac

Evaluation of Eyeball and Orbit in Relation to Gender and Age.

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Özer, Cenk Murat; Öz, Ibrahim Ilker; Şerifoğlu, Ismail; Büyükuysal, Mustafa Çağatay; Barut, Çağatay

2016-11-01

The orbital aperture is the entrance to the orbit in which most important visual structures such as the eyeball and the optic nerve are found. It is vital not only for the visual system but also for the evaluation and recognition of the face. Eyeball volume is essential for diagnosing microphthalmos or buphthalmos in several eye disorders. Knowing the length of the optic nerve is necessary in selecting the right instruments for enucleation. Therefore, the aim of this study was to evaluate eyeball volume, orbital aperture, and optic nerve dimensions for a morphological description in a Turkish population sample according to gender and body side.Paranasal sinus computed tomography (CT) scans of 198 individuals (83 females, 115 males) aged between 5 and 74 years were evaluated retrospectively. The dimensions of orbital aperture, axial length and volume of eyeball, and diameter and length of the intraorbital part of the optic nerve were measured. Computed tomography examinations were performed on an Activion 16 CT Scanner (Toshiba Medical Systems, 2008 Japan). The CT measurements were calculated by using OsiriX software on a personal computer. All parameters were evaluated according to gender and right/left sides. A statistically significant difference between genders was found with respect to axial length of eyeball, optic nerve diameter, dimensions of orbital aperture on both sides, and right optic nerve length. Furthermore, certain statistically significant side differences were also found. There were statistically significant correlations between age and the axial length of the eyeball, optic nerve diameter, and the transverse length of the orbital aperture on both sides for the whole study group.In this study we determined certain morphometric parameters of the orbit. These outcomes may be helpful in developing a database to determine normal orbit values for the Turkish population so that quantitative assessment of orbital disease and orbital deformities will be

The Nature of Age-Related Differences in Knee Function during Walking: Implication for the Development of Knee Osteoarthritis.

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Katherine A Boyer

Full Text Available Changes in knee kinematics have been identified in the early stages of osteoarthritis (OA. However, there is a paucity of information on the nature of kinematic change that occur with aging prior to the development of OA, This study applied a robust statistical method (Principal Component Analysis to test the hypothesis that coupling between primary (flexion and secondary (anterior-posterior translation, internal-external rotation joint motions in walking would differ for age groupings of healthy subjects.Seventy-four healthy participants divided into three groups with mean ages of 24 ± 2.3 years (younger, 48 ± 4.7years (middle-age and 64 ± 2.4 years (older were examined. Principal Component Analysis was used to characterize and statistically compare the patterns of knee joint movement and their relationships in walking.There were significant differences between the younger group and both the middle-age and older groups in the knee frontal plane angle and the coupling between knee flexion (PC1, p≤0.04 and the relative magnitudes of secondary plane motions in early and late stance (PC3, p<0.01. Two additional principal components (PC2, p = 0.03 and PC5, p<0.01 described differences in early stance knee flexion and relationship with secondary plane motion through-out stance for the older compared with middle-age group.It appears there are changes in knee kinematics that occur with aging. The kinematic differences were identified for middle-aged as well as older adults suggesting midlife changes in neuromuscular physiology or behavior may have important consequences. These kinematic measures offer the potential to identify early markers for the risk of developing knee OA with aging.

Familial Aggregation of Age-Related Hearing Loss in an Epidemiological Study of Older Adults

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Raynor, Laura A.; Pankow, James S.; Miller, Michael B.; Huang, Guan-Hua; Dalton, Dayna; Klein, Ronald; Klein, Barbara E. K.; Cruickshanks, Karen J.

2010-01-01

Purpose To estimate the genetic contributions to presbycusis Method Presbycusis was assessed by audiometric measurements at three waves of the population-based Epidemiology of Hearing Loss Study (EHLS). Measurements from the most recent hearing examination were used, at which time subjects were between 48 and 100 years of age. Heritability of presbycusis was estimated using maximum likelihood methods in 973 biological relative pairs from 376 families. Familial aggregation was also evaluated by tetrachoric correlations, odds ratios, and lambda statistics in 594 sibling pairs from 373 sibships. Subjects 3,510 participants from the EHLS study Results The prevalence of presbycusis conformed to previous research, increasing with age and male sex. Heritability estimates for presbycusis adjusted for age, sex, education level, and exposure to work noise exceeded 50%, and siblings of an affected relative were at 30% higher risk. When stratified by sex, estimates of familial aggregation were higher in women than men. Conclusions There is evidence that genetic factors contribute to age-related hearing loss in this population-based sample. The familial aggregation is stronger in women than in men. PMID:19474454

Power, effects, confidence, and significance: an investigation of statistical practices in nursing research.

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Gaskin, Cadeyrn J; Happell, Brenda

2014-05-01

improvement. Most importantly, researchers should abandon the misleading practice of interpreting the results from inferential tests based solely on whether they are statistically significant (or not) and, instead, focus on reporting and interpreting effect sizes, confidence intervals, and significance levels. Nursing researchers also need to conduct and report a priori power analyses, and to address the issue of Type I experiment-wise error inflation in their studies. Crown Copyright © 2013. Published by Elsevier Ltd. All rights reserved.

Sustainable employability in shiftwork: related to types of work schedule rather than age.

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Peters, Velibor; Engels, Josephine A; de Rijk, Angelique E; Nijhuis, Frans J N

2015-10-01

There is scarce research on age and sustainable employability of nurses working in various types of work schedules. Earlier research showed that nurses working in work schedules differ regarding age. Different operationalisations of age might explain variations in sustainable employability. Therefore, the aim of this study was to investigate how nurses working in various types of work schedule differ regarding sustainable employability, and the role that age plays in these differences. Age was defined as chronological age, organisational age, life-span age, and functional age. Questionnaires were distributed to 974 Dutch nurses in residential elder care (response rate 51 %) with questions about the type of work schedule, aspects of sustainable employability, various operationalisations of age, and registered sickness absence data were used. Nurses working in various types of work schedules differed regarding aspects of sustainable employability, also when operationalisations of age were added. The 'life-span age' was directly related to aspects of sustainable employability. Statistically, work ability and job satisfaction were only explained by varying operationalisations of age. Nurses' sustainable employability appeared to be mainly related to differences between the types of work schedule rather than age. Fixed early shifts are characterised by the most positive aspects of sustainable employability, and three rotating schedules score worst. To improve sustainable employability, organisations should implement a system in which nurses with different types of work schedule are monitored in combination with their life-span perspective.

Pleiotropic Meta-Analyses of Longitudinal Studies Discover Novel Genetic Variants Associated with Age-Related Diseases

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Liang He

2016-10-01

Full Text Available Age-related diseases may result from shared biological mechanisms in intrinsic processes of aging. Genetic effects on age-related diseases are often modulated by environmental factors due to their little contribution to fitness or are mediated through certain endophenotypes. Identification of genetic variants with pleiotropic effects on both common complex diseases and endophenotypes may reveal potential conflicting evolutionary pressures and deliver new insights into shared genetic contribution to healthspan and lifespan. Here, we performed pleiotropic meta-analyses of genetic variants using five NIH-funded datasets by integrating univariate summary statistics for age-related diseases and endophenotypes. We investigated three groups of traits: (1 endophenotypes such as blood glucose, blood pressure, lipids, hematocrit, and body mass index, (2 time-to-event outcomes such as the age-at-onset of diabetes mellitus (DM, cancer, cardiovascular diseases (CVDs and neurodegenerative diseases (NDs, and (3 both combined. In addition to replicating previous findings, we identify seven novel genome-wide significant loci (< 5e-08, out of which five are low-frequency variants. Specifically, from Group 2, we find rs7632505 on 3q21.1 in SEMA5B, rs460976 on 21q22.3 (1 kb from TMPRSS2 and rs12420422 on 11q24.1 predominantly associated with a variety of CVDs, rs4905014 in ITPK1 associated with stroke and heart failure, rs7081476 on 10p12.1 in ANKRD26 associated with multiple diseases including DM, CVDs, and NDs. From Group 3, we find rs8082812 on 18p11.22 and rs1869717 on 4q31.3 associated with both endophenotypes and CVDs. Our follow-up analyses show that rs7632505, rs4905014, and rs8082812 have age-dependent effects on coronary heart disease or stroke. Functional annotation suggests that most of these SNPs are within regulatory regions or DNase clusters and in linkage disequilibrium with expression quantitative trait loci, implying their potential regulatory

Longitudinal Mediation of Processing Speed on Age-Related Change in Memory and Fluid Intelligence

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Robitaille, Annie; Piccinin, Andrea M.; Muniz, Graciela; Hoffman, Lesa; Johansson, Boo; Deeg, Dorly J.H.; Aartsen, Marja J.; Comijs, Hannie C.; Hofer, Scott M.

2014-01-01

Age-related decline in processing speed has long been considered a key driver of cognitive aging. While the majority of empirical evidence for the processing speed hypothesis has been obtained from analyses of between-person age differences, longitudinal studies provide a direct test of within-person change. Using recent developments in longitudinal mediation analysis, we examine the speed–mediation hypothesis at both the within- and between-person levels in two longitudinal studies, LASA and OCTO-Twin. We found significant within-person indirect effects of change in age, such that increasing age was related to lower speed which, in turn, relates to lower performance across repeated measures on other cognitive outcomes. Although between-person indirect effects were also significant in LASA, they were not in OCTO-Twin. These differing magnitudes of direct and indirect effects across levels demonstrate the importance of separating between- and within-person effects in evaluating theoretical models of age-related change. PMID:23957224

Age-related brain atrophy and mental deterioration - a study with computed tomography

International Nuclear Information System (INIS)

Ito, M.; Hatazawa, J.; Yamaura, H.; Matsuzawa, T.

1981-01-01

The relation of brain atrophy measured with computed tomography (CT) to mental deterioration on living people was studied. A newly improved technique for quantitative measurement of brain atrophy was developed. The pixels inside the head slices were divided into three parts; brain skull, and cerebrospinal fluid according to their CT number. The volume of brain, CSF, and cranial cavity were calculated by counting the number of pixels of each tissue. Results from 130 normal brains showed that the CSF volume was constant at about 16 ml through 20-39 years old. After 40 years the mean CSF volume increased drastically and reached 71 ml in the seventies. The volume of the brain was standardized for comparison between different-sized heads (brain volume index: BVI). The mean BVI decreased with statistical significance after 40 years of age. Mental function of these persons were evaluated using Hasegawa's dementia rating scale for the elderly. Progression of brain atrophy accompanied loss of mental activities (p<0.01). (author)

[Pharmacological therapy of age-related macular degeneration based on etiopathogenesis].

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Fischer, Tamás

2015-11-15

It is of great therapeutic significance that disordered function of the vascular endothelium which supply the affected ocular structures plays a major role in the pathogenesis and development of age-related macular degeneration. Chronic inflammation is closely linked to diseases associated with endothelial dysfunction, and age-related macular degeneration is accompanied by a general inflammatory response. According to current concept, age-related macular degeneration is a local manifestation of systemic vascular disease. This recognition could have therapeutic implications because restoration of endothelial dysfunction can restabilize the condition of chronic vascular disease including age-related macular degeneration as well. Restoration of endothelial dysfunction by pharmaacological or non pharmacological interventions may prevent the development or improve endothelial dysfunction, which result in prevention or improvement of age related macular degeneration as well. Medicines including inhibitors of the renin-angiotensin system (converting enzyme inhibitors, angiotensin-receptor blockers and renin inhibitors), statins, acetylsalicylic acid, trimetazidin, third generation beta-blockers, peroxisome proliferator-activated receptor gamma agonists, folate, vitamin D, melatonin, advanced glycation end-product crosslink breaker alagebrium, endothelin-receptor antagonist bosentan, coenzyme Q10; "causal" antioxidant vitamins, N-acetyl-cysteine, resveratrol, L-arginine, serotonin receptor agonists, tumor necrosis factor-alpha blockers, specific inhibitor of the complement alternative pathway, curcumin and doxycyclin all have beneficial effects on endothelial dysfunction. Restoration of endothelial dysfunction can restabilize chronic vascular disease including age-related macular degeneration as well. Considering that the human vascular system is consubstantial, medicines listed above should be given to patients (1) who have no macular degeneration but have risk factors

Game Related Statistics Which Discriminate Between Winning and Losing Under-16 Male Basketball Games

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Lorenzo, Alberto; Gómez, Miguel Ángel; Ortega, Enrique; Ibáñez, Sergio José; Sampaio, Jaime

2010-01-01

The aim of the present study was to identify the game-related statistics which discriminate between winning and losing teams in under-16 years old male basketball games. The sample gathered all 122 games in the 2004 and 2005 Under-16 European Championships. The game-related statistics analysed were the free-throws (both successful and unsuccessful), 2- and 3-points field-goals (both successful and unsuccessful) offensive and defensive rebounds, blocks, assists, fouls, turnovers and steals. The winning teams exhibited lower ball possessions per game and better offensive and defensive efficacy coefficients than the losing teams. Results from discriminant analysis were statistically significant and allowed to emphasize several structure coefficients (SC). In close games (final score differences below 9 points), the discriminant variables were the turnovers (SC = -0.47) and the assists (SC = 0.33). In balanced games (final score differences between 10 and 29 points), the variables that discriminated between the groups were the successful 2-point field-goals (SC = -0.34) and defensive rebounds (SC = -0. 36); and in unbalanced games (final score differences above 30 points) the variables that best discriminated both groups were the successful 2-point field-goals (SC = 0.37). These results allowed understanding that these players' specific characteristics result in a different game-related statistical profile and helped to point out the importance of the perceptive and decision making process in practice and in competition. Key points The players' game-related statistical profile varied according to game type, game outcome and in formative categories in basketball. The results of this work help to point out the different player's performance described in U-16 men's basketball teams compared with senior and professional men's basketball teams. The results obtained enhance the importance of the perceptive and decision making process in practice and in competition. PMID

Some statistical considerations related to the estimation of cancer risk following exposure to ionizing radiation

International Nuclear Information System (INIS)

Land, C.E.; Pierce, D.A.

1983-01-01

Statistical theory and methodology provide the logical structure for scientific inference about the cancer risk associated with exposure to ionizing radiation. Although much is known about radiation carcinogenesis, the risk associated with low-level exposures is difficult to assess because it is too small to measure directly. Estimation must therefore depend upon mathematical models which relate observed risks at high exposure levels to risks at lower exposure levels. Extrapolated risk estimates obtained using such models are heavily dependent upon assumptions about the shape of the dose-response relationship, the temporal distribution of risk following exposure, and variation of risk according to variables such as age at exposure, sex, and underlying population cancer rates. Expanded statistical models, which make explicit certain assumed relationships between different data sets, can be used to strengthen inferences by incorporating relevant information from diverse sources. They also allow the uncertainties inherent in information from related data sets to be expressed in estimates which partially depend upon that information. To the extent that informed opinion is based upon a valid assessment of scientific data, the larger context of decision theory, which includes statistical theory, provides a logical framework for the incorporation into public policy decisions of the informational content of expert opinion

Oxidative stress participates in age-related changes in rat lumbar intervertebral discs.

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Hou, Gang; Lu, Huading; Chen, Mingjuan; Yao, Hui; Zhao, Huiqing

2014-01-01

Aging is a major factor associated with lumber intervertebral disc degeneration, and oxidative stress is known to play an essential role in the pathogenesis of many age-related diseases. In this study, we investigated oxidative stress in intervertebral discs of Wistar rats in three different age groups: youth, adult, and geriatric. Age-related intervertebral disc changes were examined by histological analysis. In addition, oxidative stress was evaluated by assessing nitric oxide (NO), superoxide dismutase (SOD), malondialdehyde (MDA), and advanced oxidation protein products (AOPPs). Intervertebral disc, but not serum, NO concentrations significantly differed between the three groups. Serum and intervertebral disc SOD activity gradually decreased with age. Furthermore, both serum and intervertebral disc MDA and AOPP levels gradually increased with age. Our studies suggest that oxidative stress is associated with age-related intervertebral disc changes. Copyright © 2014 Elsevier Ireland Ltd. All rights reserved.

Country, age, and gender differences in the prevalence of screen-based behaviour and family-related factors among school-aged children

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Jan Pavelka

2016-09-01

Full Text Available Background: New information and communication technologies have become an important part of adolescents' everyday lives. However, the sedentary behaviour of young people in Central Europe has become more similar to that found in Western European countries. This study can provide baseline data for a future comparison and investigation of lifestyle and health behaviours in this region in the future. Objective: The aim of this study is to assess country, age, and gender differences in the prevalence of sedentary behaviour activities and family-related factors among school-aged children. Methods: Using the methodology of the Health Behaviour in School-aged Children (HBSC study was performed in 2013, collecting data from 11- and 15-year-old Slovak (n = 488 and Czech (n = 418 children. The data was explored using c2 tests to determine statistical significance. Results: Two-thirds of the respondents watch television or use a computer for at least two hours a day. The older children (older vs. younger: 73.6% vs. 53.9%, c2 = 35.6, p < .001 spent excessive amounts of time watching television. More than half of the children have a television (51.9% or a computer (73.0% in their bedroom. More than half of their parents rarely or never apply rules about how long they can watch TV (63.9% or time spent on the computer (55.5%. The Slovak children reported watching television together with their parents every day significantly more frequently than their Czech peers (Slovak vs. Czech children 31.0% vs. 18.7%, c2 = 17.9, p < .001. Conclusions: The prevalence of screen-based behaviour is relatively high, as is screen time spent together with parents, especially among the Slovak children. Moreover, many children reported that their parents rarely or never applied rules about the length and content of their television watching or time spent on the computer.

Reducing statistics anxiety and enhancing statistics learning achievement: effectiveness of a one-minute strategy.

Science.gov (United States)

Chiou, Chei-Chang; Wang, Yu-Min; Lee, Li-Tze

2014-08-01

Statistical knowledge is widely used in academia; however, statistics teachers struggle with the issue of how to reduce students' statistics anxiety and enhance students' statistics learning. This study assesses the effectiveness of a "one-minute paper strategy" in reducing students' statistics-related anxiety and in improving students' statistics-related achievement. Participants were 77 undergraduates from two classes enrolled in applied statistics courses. An experiment was implemented according to a pretest/posttest comparison group design. The quasi-experimental design showed that the one-minute paper strategy significantly reduced students' statistics anxiety and improved students' statistics learning achievement. The strategy was a better instructional tool than the textbook exercise for reducing students' statistics anxiety and improving students' statistics achievement.

[Legal medicine specialists within the framework of acute care : Analysis of legal medicine consultations in relation to the victims' statistics of the state office of criminal investigation in Saxony-Anhalt].

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Pliske, G; Heide, S; Lucas, B; Brandstädter, K; Walcher, F; Kropf, S; Lessig, R; Piatek, S

2018-05-01

In acute medical care, there are patients who have been injured by the influence of others. The aim of this study was to analyze all cases which were presented to the Institute for Legal Medicine of the University Halle (Saale). The cases where analyzed in relation to the victims' statistics of the state office of criminal investigation in Saxony-Anhalt. The consultations of the Institute for Legal Medicine Halle-Wittenberg for 2012-2015 were evaluated with regard to the age and gender distribution, the reasons for the consultation and time until the request for consultations. These cases were statistically compared to the victims' statistics of the state office of criminal investigation in Saxony-Anhalt 2014-2015. A total of 536 cases (55.6% male and 44.4% female patients) were evaluated. In all, 62.1% of patients were under 18 years of age; 43.5% of all consultations were requested by pediatric (surgery) clinics. The most common reasons for consultation were sexual child abuse or violence against children (50.7%). Compared to the victims' statistics, significantly more children were examined by legal medicine specialists than could have been expected (p legal medicine specialists in relation to the victims' statistics. Most of them were children and women. The temporal latency between the act of violence and the consultations was one day and more. The latency and the renunciation of the consultation of the legal medicine specialists can lead to loss of evidence.

Age-related differences in the attention network test (ANT).

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Gamboz, Nadia; Zamarian, Stefania; Cavallero, Corrado

2010-07-01

This study investigates the effect of aging on alerting, orienting, and conflict resolution by assessing younger (mean age = 25.8) and older (mean age = 67.9) adults' performance in the Attention Network Test that combines, in a single experimental paradigm, a flanker task with alerting and orienting cues. The analyses of response times indicated equivalent orienting and conflict resolution effects in younger and older adults. By contrast, alerting was found to be significantly reduced in the elderly. This result is only marginally in accordance with recent studies addressing the issues of age-related differences in alerting, which provide mixed results. The possible role of methodological differences across studies in accounting for the controversial results concerning the aging affect on alerting is discussed.

Public opinion on age-related degradation in nuclear power plants

International Nuclear Information System (INIS)

Matsuda, Toshihiro

2005-01-01

The first objective of this study is to shed light on the public opinion on age-related degradation at nuclear power plants, namely, on how the general public recognizes or views age-related degradation, which is a safety-related issue and one of the factors contributing to accidents and failures which occur at nuclear power plants. The second objective is to look into the impacts of the accident at Mihama Unit 3, which was caused by a failure to check on the piping wall thickness, on the public opinion on age-related degradation. The first survey was conducted in August 2003, followed by the second survey in October 2004, two months after the accident. The surveys found that the age-related degradation is being perceived by people as one of the risk factors that affect the safety of nuclear power plants. The characteristics of the citizens' perceptions toward age-related degradation in the form of piping cracks are that: (a) many respondents feel uneasy but a relatively few people consider that nuclear operators are technologically capable of coping with this problem; (b) many people believe that radioactivity may be released; and (c) numerous respondents consider that signs of cracks must be thoroughly detected through inspections, while on the other hand, a large percentage of the respondents attribute the accident to improper inspections/maintenance. Based on these results, the government and nuclear operators are expected to give most illuminating explanation on the current situation of and remedial measures against age-related degradation at nuclear power plants. As for the effects of the Mihama-3 accident on the public opinion on age-related degradation, it was revealed that the accident has not so significantly affected the general view for the safety of nuclear power plants, but has newly or strongly aroused people's consciousness of two of the risk factors - improper inspections/maintenance and the age-related degradation of piping. (author)

Obesity related factors in school-aged children.

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Soltani, Parvaneh Reza; Ghanbari, Atefeh; Rad, Afagh Hasanzadeh

2013-05-01

Overweight and obesity is becoming an increasingly prevalent problem in both developed and developing world, and is one of the most serious public health challenges of the 21(st) century. Although various studies demonstrated pediatric obesity-related factors, but, due to its ongoing hazardous effects, researchers aimed to assess obesity-related factors in school-aged children in Rasht, Iran. This was a case-control study which was performed in eight primary schools of Rasht. A cluster sampling method was used to select 320 students including 80 in case (BMI ≥85(th) percentile for age and gender) and 240 in control group (BMI = 5(th)-85(th) percentile for age and gender). Data were collected by a scale, a tape meter, and a form which consisted of obesity-related factors, and were analyzed by Chi-square, Mann-Whitney, and stepwise multivariate regression tests in SPSS 19. Findings showed that the mean and standard deviation of birth weight (g) in case and control groups were 3671 ± 5.64 and 190 ± 5.46, respectively (P = 0.000). 82.5% of case and 92.9% of control group had exclusive breastfeeding for 4-6 months (P = 0.024). Also, multivariate regression analysis indicated that birth weight, age, exclusive breastfeeding, and frequency of meals have significant effects on body mass index (BMI). It seems that more accurate interventions for primordial prevention are essential to reduce childhood obesity risk factors, including promotion of pre-pregnancy and prenatal care to have neonates who are appropriate for gestational age and also improving exclusive breastfeeding in the first 6 months of life. In addition, identifying children at risk for adolescent obesity provides physicians and midwives with an opportunity for earlier intervention with the goal of limiting the progression of abnormal weight gain.

Aging and the statistical learning of grammatical form classes.

Science.gov (United States)

Schwab, Jessica F; Schuler, Kathryn D; Stillman, Chelsea M; Newport, Elissa L; Howard, James H; Howard, Darlene V

2016-08-01

Language learners must place unfamiliar words into categories, often with few explicit indicators about when and how that word can be used grammatically. Reeder, Newport, and Aslin (2013) showed that college students can learn grammatical form classes from an artificial language by relying solely on distributional information (i.e., contextual cues in the input). Here, 2 experiments revealed that healthy older adults also show such statistical learning, though they are poorer than young at distinguishing grammatical from ungrammatical strings. This finding expands knowledge of which aspects of learning vary with aging, with potential implications for second language learning in late adulthood. (PsycINFO Database Record (c) 2016 APA, all rights reserved).

Examining reproducibility in psychology : A hybrid method for combining a statistically significant original study and a replication

NARCIS (Netherlands)

Van Aert, R.C.M.; Van Assen, M.A.L.M.

2018-01-01

The unrealistically high rate of positive results within psychology has increased the attention to replication research. However, researchers who conduct a replication and want to statistically combine the results of their replication with a statistically significant original study encounter

A tutorial on hunting statistical significance by chasing N

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Denes Szucs

2016-09-01

Full Text Available There is increasing concern about the replicability of studies in psychology and cognitive neuroscience. Hidden data dredging (also called p-hacking is a major contributor to this crisis because it substantially increases Type I error resulting in a much larger proportion of false positive findings than the usually expected 5%. In order to build better intuition to avoid, detect and criticise some typical problems, here I systematically illustrate the large impact of some easy to implement and so, perhaps frequent data dredging techniques on boosting false positive findings. I illustrate several forms of two special cases of data dredging. First, researchers may violate the data collection stopping rules of null hypothesis significance testing by repeatedly checking for statistical significance with various numbers of participants. Second, researchers may group participants post-hoc along potential but unplanned independent grouping variables. The first approach 'hacks' the number of participants in studies, the second approach ‘hacks’ the number of variables in the analysis. I demonstrate the high amount of false positive findings generated by these techniques with data from true null distributions. I also illustrate that it is extremely easy to introduce strong bias into data by very mild selection and re-testing. Similar, usually undocumented data dredging steps can easily lead to having 20-50%, or more false positives.

Neutral dynamics with environmental noise: Age-size statistics and species lifetimes

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Kessler, David; Suweis, Samir; Formentin, Marco; Shnerb, Nadav M.

2015-08-01

Neutral dynamics, where taxa are assumed to be demographically equivalent and their abundance is governed solely by the stochasticity of the underlying birth-death process, has proved itself as an important minimal model that accounts for many empirical datasets in genetics and ecology. However, the restriction of the model to demographic [O (√{N }) ] noise yields relatively slow dynamics that appears to be in conflict with both short-term and long-term characteristics of the observed systems. Here we analyze two of these problems—age-size relationships and species extinction time—in the framework of a neutral theory with both demographic and environmental stochasticity. It turns out that environmentally induced variations of the demographic rates control the long-term dynamics and modify dramatically the predictions of the neutral theory with demographic noise only, yielding much better agreement with empirical data. We consider two prototypes of "zero mean" environmental noise, one which is balanced with regard to the arithmetic abundance, another balanced in the logarithmic (fitness) space, study their species lifetime statistics, and discuss their relevance to realistic models of community dynamics.

Self-reported optometric practise patterns in age-related macular degeneration.

Science.gov (United States)

Ly, Angelica; Nivison-Smith, Lisa; Zangerl, Barbara; Assaad, Nagi; Kalloniatis, Michael

2017-11-01

by optometrists. Clinically significant variations in self-rated test competency and the understanding regarding nutritional supplements for different stages of age-related macular degeneration suggest that further work to up-skill optometrists may be required. © 2017 Optometry Australia.

Age-related signal intensity changes in the corpus callosum: assessment with three orthogonal FLAIR images

Energy Technology Data Exchange (ETDEWEB)

Yamamoto, Akira; Miki, Yukio; Kanagaki, Mitsunori; Takahashi, Takahiro; Fushimi, Yasutaka; Haque, Tabassum Laz; Togashi, Kaori [Kyoto University, Department of Nuclear Medicine and Diagnostic Imaging, Graduate School of Medicine, Kyoto (Japan); Tomimoto, Hidekazu [Kyoto University, Department of Neurology, Graduate School of Medicine, Kyoto (Japan); Konishi, Junya [Kobe University, Department of Radiology, Graduate School of Medicine, Kobe, Hyogo (Japan)

2005-11-01

The presence of age-related hyperintensities of the corpus callosum has not been thoroughly evaluated. Fifty-two patients of 50 years of age or older (mean, 71 years; range, 50-87 years) were included in this study. Fluid-attenuated inversion recovery images were obtained in three orthogonal planes. Periventricular hyperintensities (PVHs) and deep white matter hyperintensities (DWMHs) were graded according to Fazekas' rating scale. Correlations between the presence of hyperintensities in the corpus callosum and age, and the grade of PVH and DWMH were statistically analyzed. PVH was categorized as grade 0 (n=4), grade 1 (n=28), grade 2 (n=10), or grade 3 (n=10). DWMH was categorized as grade 0 (n=4), grade 1 (n=25), grade 2 (n=8), or grade 3 (n=15). Hyperintensity was considered present in the corpus callosum in 31 of the 52 patients (60%). In these 31 patients, PVH was categorized as grade 1 (n=16), grade 2 (n=7), or grade 3 (n=8), while DWMH was categorized as grade 0 (n=1), grade 1 (n=10), grade 2 (n=7), or grade 3 (n=13). The presence of callosal hyperintensities was significantly correlated with age (p=0.001), and with PVH (p=0.04) and DWMH grades (p=0.004). Hyperintensities may be present in the corpus callosum with aging, and are correlated with PVH and DWMH. (orig.)

Age-related signal intensity changes in the corpus callosum: assessment with three orthogonal FLAIR images

International Nuclear Information System (INIS)

Yamamoto, Akira; Miki, Yukio; Kanagaki, Mitsunori; Takahashi, Takahiro; Fushimi, Yasutaka; Haque, Tabassum Laz; Togashi, Kaori; Tomimoto, Hidekazu; Konishi, Junya

2005-01-01

The presence of age-related hyperintensities of the corpus callosum has not been thoroughly evaluated. Fifty-two patients of 50 years of age or older (mean, 71 years; range, 50-87 years) were included in this study. Fluid-attenuated inversion recovery images were obtained in three orthogonal planes. Periventricular hyperintensities (PVHs) and deep white matter hyperintensities (DWMHs) were graded according to Fazekas' rating scale. Correlations between the presence of hyperintensities in the corpus callosum and age, and the grade of PVH and DWMH were statistically analyzed. PVH was categorized as grade 0 (n=4), grade 1 (n=28), grade 2 (n=10), or grade 3 (n=10). DWMH was categorized as grade 0 (n=4), grade 1 (n=25), grade 2 (n=8), or grade 3 (n=15). Hyperintensity was considered present in the corpus callosum in 31 of the 52 patients (60%). In these 31 patients, PVH was categorized as grade 1 (n=16), grade 2 (n=7), or grade 3 (n=8), while DWMH was categorized as grade 0 (n=1), grade 1 (n=10), grade 2 (n=7), or grade 3 (n=13). The presence of callosal hyperintensities was significantly correlated with age (p=0.001), and with PVH (p=0.04) and DWMH grades (p=0.004). Hyperintensities may be present in the corpus callosum with aging, and are correlated with PVH and DWMH. (orig.)

Aging on a different scale--chronological versus pathology-related aging.

Science.gov (United States)

Melis, Joost P M; Jonker, Martijs J; Vijg, Jan; Hoeijmakers, Jan H J; Breit, Timo M; van Steeg, Harry

2013-10-01

In the next decades the elderly population will increase dramatically, demanding appropriate solutions in health care and aging research focusing on healthy aging to prevent high burdens and costs in health care. For this, research targeting tissue-specific and individual aging is paramount to make the necessary progression in aging research. In a recently published study we have attempted to make a step interpreting aging data on chronological as well as pathological scale. For this, we sampled five major tissues at regular time intervals during the entire C57BL/6J murine lifespan from a controlled in vivo aging study, measured the whole transcriptome and incorporated temporal as well as physical health aspects into the analyses. In total, we used 18 different age-related pathological parameters and transcriptomic profiles of liver, kidney, spleen, lung and brain and created a database that can now be used for a broad systems biology approach. In our study, we focused on the dynamics of biological processes during chronological aging and the comparison between chronological and pathology-related aging.

The age-related changes in figural perceptual abilities of pupils

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Nešić Blagoje V.

2013-01-01

Full Text Available This paper is a part of a broader research in the field of development of different intellectual abilities in primary schools. Using a transverse - longitudinal research strategy, the pupils from nine to fifteen years of age are observed in order to find answers to the following questions: 1 Do the important developmental changes in the figural-perceptual abilities occur in this developmental period? 2 Is the pace of changes in these abilities the same at all ages, grades? 3 Do the developmental changes in these abilities depend on the type of tests, that is, mental operations which register the applied tests? Figural-perceptual abilities are defined as the ability to identify the elements in space, to imagine and transform the elements in space, the ability for spatial reasoning, perceptual shaping flexibility, the ability of eduction of relations and correlates, the ability to identify the elements that are injected into the right material, the ability to notice the difference in the forms and dimensions of the characters, speed observations of similarities and differences between elements in the field of perception. The measurement (assessment of these abilities was performed with the help of 11 tests of intellectual abilities of the figural content. The individual progresses as baseline data were used for the data analysis. The progresses of the subjects were compared with the analysis and the results are the following: 1 The pupils from third to eighth grade showed positive changes in the figurative perceptive abilities. This is shown in all the tests that were used and progresses are statistically significant in all tests 2 There is a tendency that the pupils in the sixth grade made the best progress, and the seventh-grade pupils made the least progress. 3 However, when the progresses are compared in certain tests, then significant differences in the pace of development of these abilities are determined. Namely, the pupils in the higher

Gender differences in age-related decline in regional cerebral glucose metabolism

International Nuclear Information System (INIS)

Bang, Seong Ae; Cho, Sang Soo; Yoon, Eun Jin; Park, Hyun Soo; Lee, Eun Ju; Kim, Yu Kyeong; Kim, Sang Sun

2007-01-01

In this study, we investigated gender differences in age-related declines in regional cerebral glucose metabolism using FDG-PET in a large population sample with a broad age range. 230 healthy subjects (90 male; age: 34-80 y, 140 females; age: 33-82 y) participated. Correlation maps showing age related declines in glucose uptake were created separately for each gender in SPM2. Using population-based probabilistic volume of interests (VOIs), VOIs were defined for the regions showing significant decline with aging. Age related declines were separately assessed within each age range using analysis of covariate in SPSS 13.0. In the total population without gender effect, age-related negative correlation of glucose metabolism was found in the bilateral inferior frontal gyri, bilateral caudate, bilateral thalamus, left insula, left superior frontal gyrus, left uncus, right superior temporal gyrus, right medial frontal gyrus, right parahippocampal gyrus, right anterior cingulate gyrus (P < 0.001 corrected, extent threshold k = 100). 14 VOIs values of brain regions were calculated based on this negative correlation results. The rate of decline across all defined VOIs assessed in the age category of 'more than 70' referenced to the category of '30- 39years' were 7.85% in the entire sample; 7.62% in male and 8.09% in female. Detailed analyses of declines in each age range showed separable patterns of declines across gender. In males, greater decline was observed after the age 60 (20.45%) than the ages of 30 and 50(7.98%). Whereas in females, greater declines were found in age 60s (20.15%) compared to 50s, and in 40(14.84%) compared to 30s. Age-related decline in cerebral glucose metabolism was found in both genders. We further observed that males show a relatively constant pattern of decline across a life span; whereas, females show a pattern of steep changes aging to 60s and to 40s, which may be related to changes in sex hormone levels after menopause

Gender differences in age-related decline in regional cerebral glucose metabolism

Energy Technology Data Exchange (ETDEWEB)

Bang, Seong Ae; Cho, Sang Soo; Yoon, Eun Jin; Park, Hyun Soo; Lee, Eun Ju; Kim, Yu Kyeong; Kim, Sang Sun [Seoul National Univ. College of Medicine, Seoul (Korea, Republic of)

2007-07-01

In this study, we investigated gender differences in age-related declines in regional cerebral glucose metabolism using FDG-PET in a large population sample with a broad age range. 230 healthy subjects (90 male; age: 34-80 y, 140 females; age: 33-82 y) participated. Correlation maps showing age related declines in glucose uptake were created separately for each gender in SPM2. Using population-based probabilistic volume of interests (VOIs), VOIs were defined for the regions showing significant decline with aging. Age related declines were separately assessed within each age range using analysis of covariate in SPSS 13.0. In the total population without gender effect, age-related negative correlation of glucose metabolism was found in the bilateral inferior frontal gyri, bilateral caudate, bilateral thalamus, left insula, left superior frontal gyrus, left uncus, right superior temporal gyrus, right medial frontal gyrus, right parahippocampal gyrus, right anterior cingulate gyrus (P < 0.001 corrected, extent threshold k = 100). 14 VOIs values of brain regions were calculated based on this negative correlation results. The rate of decline across all defined VOIs assessed in the age category of 'more than 70' referenced to the category of '30- 39years' were 7.85% in the entire sample; 7.62% in male and 8.09% in female. Detailed analyses of declines in each age range showed separable patterns of declines across gender. In males, greater decline was observed after the age 60 (20.45%) than the ages of 30 and 50(7.98%). Whereas in females, greater declines were found in age 60s (20.15%) compared to 50s, and in 40(14.84%) compared to 30s. Age-related decline in cerebral glucose metabolism was found in both genders. We further observed that males show a relatively constant pattern of decline across a life span; whereas, females show a pattern of steep changes aging to 60s and to 40s, which may be related to changes in sex hormone levels after menopause.

Female age-related fertility decline. Committee Opinion No. 589.

Science.gov (United States)

2014-03-01

The fecundity of women decreases gradually but significantly beginning approximately at age 32 years and decreases more rapidly after age 37 years. Education and enhanced awareness of the effect of age on fertility are essential in counseling the patient who desires pregnancy. Given the anticipated age-related decline in fertility, the increased incidence of disorders that impair fertility, and the higher risk of pregnancy loss, women older than 35 years should receive an expedited evaluation and undergo treatment after 6 months of failed attempts to conceive or earlier, if clinically indicated. In women older than 40 years, more immediate evaluation and treatment are warranted. Copyright © 2014 American Society for Reproductive Medicine. Published by Elsevier Inc. All rights reserved.

Statins for age-related macular degeneration.

Science.gov (United States)

Gehlbach, Peter; Li, Tianjing; Hatef, Elham

2015-02-11

Age-related macular degeneration (AMD) is a progressive late onset disorder of the macula affecting central vision. Age-related macular degeneration is the leading cause of blindness in people over 65 years in industrialized countries. Recent epidemiologic, genetic, and pathological evidence has shown AMD shares a number of risk factors with atherosclerosis, leading to the hypothesis that statins may exert protective effects in AMD. The objective of this review was to examine the effectiveness of statins compared with other treatments, no treatment, or placebo in delaying the onset and progression of AMD. We searched CENTRAL (which contains the Cochrane Eyes and Vision Group Trials Register) (2014, Issue 6), Ovid MEDLINE, Ovid MEDLINE In-Process and Other Non-Indexed Citations, Ovid MEDLINE Daily, Ovid OLDMEDLINE (January 1946 to June 2014), EMBASE (January 1980 to June 2014), Latin American and Caribbean Health Sciences Literature Database (LILACS) (January 1982 to June 2014), PubMed (January 1946 to June 2014), the metaRegister of Controlled Trials (mRCT) (www.controlled-trials.com), ClinicalTrials.gov (www.clinicaltrials.gov), and the WHO International Clinical Trials Registry Platform (ICTRP) (www.who.int/ictrp/search/en). We did not use any date or language restrictions in the electronic searches for trials. We last searched the electronic databases on 5 June 2014. We included randomized controlled trials (RCTs) that compared statins with other treatments, no treatment, or placebo in participants who were either susceptible to or diagnosed as having early stages of AMD. We used standard methodological procedures expected by The Cochrane Collaboration. Two authors independently evaluated the search results against the selection criteria, abstracted data, and assessed risk of bias. We did not perform meta-analysis due to heterogeneity in the interventions and outcomes among the included studies. Two RCTs with 144 total participants met the selection criteria

Efficacy of a composite biological age score to predict ten-year survival among Kansas and Nebraska Mennonites.

Science.gov (United States)

Uttley, M; Crawford, M H

1994-02-01

In 1980 and 1981 Mennonite descendants of a group of Russian immigrants participated in a multidisciplinary study of biological aging. The Mennonites live in Goessel, Kansas, and Henderson, Nebraska. In 1991 the survival status of the participants was documented by each church secretary. Data are available for 1009 individuals, 177 of whom are now deceased. They ranged from 20 to 95 years in age when the data were collected. Biological ages were computed using a stepwise multiple regression procedure based on 38 variables previously identified as being related to survival, with chronological age as the dependent variable. Standardized residuals place participants in either a predicted-younger or a predicted-older group. The independence of the variables biological age and survival status is tested with the chi-square statistic. The significance of biological age differences between surviving and deceased Mennonites is determined by t test values. The two statistics provide consistent results. Predicted age group classification and survival status are related. The group of deceased participants is generally predicted to be older than the group of surviving participants, although neither statistic is significant for all subgroups of Mennonites. In most cases, however, individuals in the predicted-older groups are at a relatively higher risk of dying compared with those in the predicted-younger groups, although the increased risk is not always significant.

Size, shape and age-related changes of the mandibular condyle during childhood

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Karlo, Christoph A. [University Children' s Hospital Zurich, Department of Diagnostic Imaging, Zurich (Switzerland); University Hospital Zurich, Institute of Diagnostic and Interventional Radiology, Zurich (Switzerland); Stolzmann, Paul [University Hospital Zurich, Institute of Diagnostic and Interventional Radiology, Zurich (Switzerland); Habernig, Sandra; Kellenberger, Christian J. [University Children' s Hospital Zurich, Department of Diagnostic Imaging, Zurich (Switzerland); Mueller, Lukas [University of Zurich, Clinics for Orthodontics and Paediatric Dentistry, Zurich (Switzerland); Saurenmann, Traudel [University Children' s Hospital Zurich, Department of Rheumatology, Zurich (Switzerland)

2010-10-15

To determine age-related differences in the size and shape of the mandibular condyle in children to establish anatomical reference values. A total of 420 mandibular condyles in 210 children (mean age, 7 years) were retrospectively analysed by using computed tomography (CT) imaging. The greatest left-right (LRD) and anterior-posterior (APD) diameters and the anteversion angles (AA) were measured by two readers. An APD/LRD ratio was calculated. The shape of the condyles was graded into three types on sagittal images. Correlations of parameters with the children's age were assessed by using Pearson's correlation analyses. The LRD (mean, 14.1 {+-} 2.4 mm), APD (mean, 7.3 {+-} 1.0 mm) and LRD/APD ratio (mean, 1.9 {+-} 0.3) increased (r{sub LRD} = 0.70, p < 0.01; r{sub APD} = 0.56, p < 0.01; r{sub rat} = 0.28, p < 0.01) while the AA (mean, 27 {+-} 7 ) decreased significantly (r{sub antang} = -0.26, p < 0.001) with age. The condylar shape as determined on sagittal images correlated significantly with age (r = 0.69, p < 0.05). Boys had significantly higher anteversion angles (p < 0.01), greater LRDs (p < 0.05) and greater mean ratios (p < 0.05). The mandibular condyle is subject to significant age-related changes in size and shape during childhood. As the size of the condyles increases with age, the anteversion angles decrease and the shape of the condyle turns from round to oval. (orig.)

Age most significant predictor of requiring enteral feeding in head-and-neck cancer patients

International Nuclear Information System (INIS)

Sachdev, Sean; Refaat, Tamer; Bacchus, Ian D; Sathiaseelan, Vythialinga; Mittal, Bharat B

2015-01-01

A significant number of patients treated for head and neck squamous cell cancer (HNSCC) undergo enteral tube feeding. Data suggest that avoiding enteral feeding can prevent long-term tube dependence and disuse of the swallowing mechanism which has been linked to complications such as prolonged dysphagia and esophageal constriction. We examined detailed dosimetric and clinical parameters to better identify those at risk of requiring enteral feeding. One hundred patients with advanced stage HNSCC were retrospectively analyzed after intensity-modulated radiation therapy (IMRT) to a median dose of 70 Gy (range: 60-75 Gy) with concurrent chemotherapy in nearly all cases (97%). Patients with significant weight loss (>10%) in the setting of severely reduced oral intake were referred for placement of a percutaneous endoscopic gastrostomy (PEG) tube. Detailed DVH parameters were collected for several structures. Univariate and multivariate analyses using logistic regression were used to determine clinical and dosimetric factors associated with needing enteral feeding. Dichotomous outcomes were tested using Fisher’s exact test and continuous variables between groups using the Wilcoxon rank-sum test. Thirty-three percent of patients required placement of an enteral feeding tube. The median time to tube placement was 25 days from start of treatment, after a median dose of 38 Gy. On univariate analysis, age (p = 0.0008), the DFH (Docetaxel/5-FU/Hydroxyurea) chemotherapy regimen (p = .042) and b.i.d treatment (P = 0.040) (used in limited cases on protocol) predicted need for enteral feeding. On multivariate analysis, age remained the single statistically significant factor (p = 0.003) regardless of other clinical features (e.g. BMI) and all radiation planning parameters. For patients 60 or older compared to younger adults, the odds ratio for needing enteral feeding was 4.188 (p = 0.0019). Older age was found to be the most significant risk factor for needing enteral feeding in

The role of hydrogen sulfide in aging and age-related pathologies.

Science.gov (United States)

Perridon, Bernard W; Leuvenink, Henri G D; Hillebrands, Jan-Luuk; van Goor, Harry; Bos, Eelke M

2016-09-27

When humans grow older, they experience inevitable and progressive loss of physiological function, ultimately leading to death. Research on aging largely focuses on the identification of mechanisms involved in the aging process. Several proposed aging theories were recently combined as the 'hallmarks of aging'. These hallmarks describe (patho-)physiological processes that together, when disrupted, determine the aging phenotype. Sustaining evidence shows a potential role for hydrogen sulfide (H 2 S) in the regulation of aging. Nowadays, H 2 S is acknowledged as an endogenously produced signaling molecule with various (patho-) physiological effects. H 2 S is involved in several diseases including pathologies related to aging. In this review, the known, assumed and hypothetical effects of hydrogen sulfide on the aging process will be discussed by reviewing its actions on the hallmarks of aging and on several age-related pathologies.

Age-Related Effects of Stimulus Type and Congruency on Inattentional Blindness.

Science.gov (United States)

Liu, Han-Hui

2018-01-01

Background: Most of the previous inattentional blindness (IB) studies focused on the factors that contributed to the detection of unattended stimuli. The age-related changes on IB have rarely been investigated across all age groups. In the current study, by using the dual-task IB paradigm, we aimed to explore the age-related effects of attended stimuli type and congruency between attended and unattended stimuli on IB. Methods: The current study recruited 111 participants (30 adolescents, 48 young adults, and 33 middle-aged adults) in the baseline recognition experiments and 341 participants (135 adolescents, 135 young adults, and 71 middle-aged adults) in the IB experiment. We applied the superimposed picture and word streams experimental paradigm to explore the age-related effects of attended stimuli type and congruency between attended and unattended stimuli on IB. An ANOVA was performed to analyze the results. Results: Participants across all age groups presented significantly lower recognition scores for both pictures and words in comparison with baseline recognition. Participants presented decreased recognition for unattended pictures or words from adolescents to young adults and middle-aged adults. When the pictures and words are congruent, all the participants showed significantly higher recognition scores for unattended stimuli in comparison with incongruent condition. Adolescents and young adults did not show recognition differences when primary tasks were attending pictures or words. Conclusion: The current findings showed that all participants presented better recognition scores for attended stimuli in comparison with unattended stimuli, and the recognition scores decreased from the adolescents to young and middle-aged adults. The findings partly supported the attention capacity models of IB.

Age-Related Effects of Stimulus Type and Congruency on Inattentional Blindness

Directory of Open Access Journals (Sweden)

Han-Hui Liu

2018-05-01

Full Text Available Background: Most of the previous inattentional blindness (IB studies focused on the factors that contributed to the detection of unattended stimuli. The age-related changes on IB have rarely been investigated across all age groups. In the current study, by using the dual-task IB paradigm, we aimed to explore the age-related effects of attended stimuli type and congruency between attended and unattended stimuli on IB.Methods: The current study recruited 111 participants (30 adolescents, 48 young adults, and 33 middle-aged adults in the baseline recognition experiments and 341 participants (135 adolescents, 135 young adults, and 71 middle-aged adults in the IB experiment. We applied the superimposed picture and word streams experimental paradigm to explore the age-related effects of attended stimuli type and congruency between attended and unattended stimuli on IB. An ANOVA was performed to analyze the results.Results: Participants across all age groups presented significantly lower recognition scores for both pictures and words in comparison with baseline recognition. Participants presented decreased recognition for unattended pictures or words from adolescents to young adults and middle-aged adults. When the pictures and words are congruent, all the participants showed significantly higher recognition scores for unattended stimuli in comparison with incongruent condition. Adolescents and young adults did not show recognition differences when primary tasks were attending pictures or words.Conclusion: The current findings showed that all participants presented better recognition scores for attended stimuli in comparison with unattended stimuli, and the recognition scores decreased from the adolescents to young and middle-aged adults. The findings partly supported the attention capacity models of IB.

Relative age effect on success in tennis competition in the older age-school children

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Adrián Agricola

2015-06-01

Full Text Available BACKGROUND: The theory of relative age effect assumes that children and adolescents - athletes born at the beginning of the calendar year in sports competitions are more successful than those who were born in the later months of the same year. This percentage is based on advantage of fitness, morphological and psychological assumptions of the older athletes. AIM: The research objective of the present study was to verify the assumption of competitive success of older players in the elite boys and girls tennis groups in the older school age. METHODOLOGY: The data from groups of 13 year old boys and girls (13 years and 0 months to 13 years and 11 months were included into the analysis. These players were registered in the first one hundred ranking of International Tennis Federation (ITF according to the total number of ranking points in each year during the period 2007-2011 (500 boys, 500 girls. An ANOVA was used for analysis with a total ranking score as an indicator of competitive success with the age factor (12 levels = 12 months of birth (α = .05. The same analysis was used in sub-groups of boys, respectively girls, registered in ITF separately for each year of the period 2007-2011. Dates of birth of children were obtained from official sources of ITF. In the event of the significance factor of age we performed a simple regression analysis depending on the number of ITF points on the month of birth (p < .05. Analyses were processed in SPSS 21 software (IBM, USA. RESULTS: The analysis showed no significance of age, respective of the month of birth on the total number of points in a boys group (n = 500 (p = .624 and girls group (n = 500 (p = .152 from ITF ranking during five-year period. No significance was found in the boys' groups (n = 100, respective girls' groups (n = 100 registered in ITF ranking in each year of the five-year period. The exception was found only in a boys group in 2007 (p = .021, and significant regression relationship

Glucose and age-related changes in memory.

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Gold, Paul E

2005-12-01

Epinephrine, released from the adrenal medulla, enhances memory in young rats and mice and apparently does so, at least in part, by increasing blood glucose levels. Like epinephrine, administration of glucose enhances cognitive functions in humans and rodents, including reversing age-related impairments in learning and memory. Epinephrine responses to training are increased in aged rats but the subsequent increase in blood glucose levels is severely blunted. The absence of increases in blood glucose levels during training might contribute to age-related deficits in learning and memory. Also, extracellular glucose levels in the hippocampus are depleted during spontaneous alternation testing to a far greater extent in aged than in young rats. Importantly, systemic injections of glucose block the depletion in the hippocampus and also enhance performance on the alternation task. Thus, the extensive depletion of extracellular glucose during training in aged rats may be associated with age-related memory impairments, an effect that might be related to - or may exacerbate - the effects on learning and memory of an absence of the increases in blood glucose levels to training as seen in young rats. Together, these findings suggest that age-related changes in both peripheral and central glucose physiology contribute to age-related impairments in memory.

Age-related changes in visual temporal order judgment performance: Relation to sensory and cognitive capacities.

Science.gov (United States)

Busey, Thomas; Craig, James; Clark, Chris; Humes, Larry

2010-08-06

Five measures of temporal order judgments were obtained from 261 participants, including 146 elder, 44 middle aged, and 71 young participants. Strong age group differences were observed in all five measures, although the group differences were reduced when letter discriminability was matched for all participants. Significant relations were found between these measures of temporal processing and several cognitive and sensory assays, and structural equation modeling revealed the degree to which temporal order processing can be viewed as a latent factor that depends in part on contributions from sensory and cognitive capacities. The best-fitting model involved two different latent factors representing temporal order processing at same and different locations, and the sensory and cognitive factors were more successful predicting performance in the different location factor than the same-location factor. Processing speed, even measured using high-contrast symbols on a paper-and-pencil test, was a surprisingly strong predictor of variability in both latent factors. However, low-level sensory measures also made significant contributions to the latent factors. The results demonstrate the degree to which temporal order processing relates to other perceptual and cognitive capacities, and address the question of whether age-related declines in these capacities share a common cause. Copyright 2010 Elsevier Ltd. All rights reserved.

Statistical mechanics in the context of special relativity.

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Kaniadakis, G

2002-11-01

In Ref. [Physica A 296, 405 (2001)], starting from the one parameter deformation of the exponential function exp(kappa)(x)=(sqrt[1+kappa(2)x(2)]+kappax)(1/kappa), a statistical mechanics has been constructed which reduces to the ordinary Boltzmann-Gibbs statistical mechanics as the deformation parameter kappa approaches to zero. The distribution f=exp(kappa)(-beta E+betamu) obtained within this statistical mechanics shows a power law tail and depends on the nonspecified parameter beta, containing all the information about the temperature of the system. On the other hand, the entropic form S(kappa)= integral d(3)p(c(kappa) f(1+kappa)+c(-kappa) f(1-kappa)), which after maximization produces the distribution f and reduces to the standard Boltzmann-Shannon entropy S0 as kappa-->0, contains the coefficient c(kappa) whose expression involves, beside the Boltzmann constant, another nonspecified parameter alpha. In the present effort we show that S(kappa) is the unique existing entropy obtained by a continuous deformation of S0 and preserving unaltered its fundamental properties of concavity, additivity, and extensivity. These properties of S(kappa) permit to determine unequivocally the values of the above mentioned parameters beta and alpha. Subsequently, we explain the origin of the deformation mechanism introduced by kappa and show that this deformation emerges naturally within the Einstein special relativity. Furthermore, we extend the theory in order to treat statistical systems in a time dependent and relativistic context. Then, we show that it is possible to determine in a self consistent scheme within the special relativity the values of the free parameter kappa which results to depend on the light speed c and reduces to zero as c--> infinity recovering in this way the ordinary statistical mechanics and thermodynamics. The statistical mechanics here presented, does not contain free parameters, preserves unaltered the mathematical and epistemological structure of

Age and muscle strength mediate the age-related biomechanical plasticity of gait

NARCIS (Netherlands)

Hortobagyi, Tibor; Rider, Patrick; Gruber, Allison H.; DeVita, Paul

Old compared with young adults walk with reduced ankle and increased hip mechanical output. We examined the idea that age, leg strength, or both are related to the age-related changes in mechanical output during gait. Healthy young (n = 32, age 21.5 years) and old adults (n = 32, age 76.8 years)

Factors related to the effect of radiation treatment for age-related macular degeneration

International Nuclear Information System (INIS)

Mandai, Michiko; Takahashi, Masayo; Matsumura, Miyo; Sasai, Keisuke; Honda, Yoshihito; Ogura, Yuichiro

2000-01-01

We treated 31 eyes of 30 patients with age-related macular degeneration by 10 sessions of radiation totalling 20 Gy. One year after treatment, 21 eyes (68%) showed improvement in the score of fundus lesions based on funduscopic and fluorescein angiographic findings. The visual acuity, expressed as LogMAR, improved in 20% and remained stationary in 50% of eyes. Improvement in visual acuity was significantly better in eyes with greater amount of exudate before treatment (p<0.01). Posttreatment visual acuity was correlated neither with the amount of subretinal fluid, presence of retinal hemorrhage, the size of subfoveal vascular membrane, nor its type as classified into classic, mainly occult or occult type. Above findings show that radiation is more effective in eyes of age-related macular degeneration with massive exudate. (author)

Factors related to the effect of radiation treatment for age-related macular degeneration

Energy Technology Data Exchange (ETDEWEB)

Mandai, Michiko; Takahashi, Masayo; Matsumura, Miyo; Sasai, Keisuke; Honda, Yoshihito [Kyoto Univ. (Japan). Graduate School of Medicine; Ogura, Yuichiro

2000-04-01

We treated 31 eyes of 30 patients with age-related macular degeneration by 10 sessions of radiation totalling 20 Gy. One year after treatment, 21 eyes (68%) showed improvement in the score of fundus lesions based on funduscopic and fluorescein angiographic findings. The visual acuity, expressed as LogMAR, improved in 20% and remained stationary in 50% of eyes. Improvement in visual acuity was significantly better in eyes with greater amount of exudate before treatment (p<0.01). Posttreatment visual acuity was correlated neither with the amount of subretinal fluid, presence of retinal hemorrhage, the size of subfoveal vascular membrane, nor its type as classified into classic, mainly occult or occult type. Above findings show that radiation is more effective in eyes of age-related macular degeneration with massive exudate. (author)

Age-Associated Changes in the Spectral and Statistical Parameters of Surface Electromyogram of Tibialis Anterior.

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Siddiqi, Ariba; Arjunan, Sridhar Poosapadi; Kumar, Dinesh Kant

2016-01-01

Age-related neuromuscular change of Tibialis Anterior (TA) is a leading cause of muscle strength decline among the elderly. This study has established the baseline for age-associated changes in sEMG of TA at different levels of voluntary contraction. We have investigated the use of Gaussianity and maximal power of the power spectral density (PSD) as suitable features to identify age-associated changes in the surface electromyogram (sEMG). Eighteen younger (20-30 years) and 18 older (60-85 years) cohorts completed two trials of isometric dorsiflexion at four different force levels between 10% and 50% of the maximal voluntary contraction. Gaussianity and maximal power of the PSD of sEMG were determined. Results show a significant increase in sEMG's maximal power of the PSD and Gaussianity with increase in force for both cohorts. It was also observed that older cohorts had higher maximal power of the PSD and lower Gaussianity. These age-related differences observed in the PSD and Gaussianity could be due to motor unit remodelling. This can be useful for noninvasive tracking of age-associated neuromuscular changes.

Computed tomographic features of the feline brain change with advancing age?

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Viviam R. Babicsak

2015-12-01

Full Text Available Abstract: A better understanding of normal or expected encephalic changes with increasing age in cats is needed as a growing number of these animals is attended in veterinary clinics, and imaging data referring to normal age-associated changes are extremely scarce in the literature. The objective of this study was to identify age-related changes in feline brain using CT imaging. Fifteen non-brachycephalic healthy cats with age between 1 to 6 years (adult group and others over 12 years (geriatric group were submitted to CT scan of the brain. Statistically significant differences were found between the groups for the ability to identify the left lateral ventricle and for falx cerebri calcification, both identified in a greater number of cats of the geriatric group. A significantly higher mean width of the third ventricle was also detected in geriatric animals. There were no statistically significant differences between lateral ventricular dimensions and encephalic parenchymal attenuation on pre and post-contrast CT phases. The results of the present study show an increase in the incidence of falx cerebri calcification and a third ventricular dilatation with advancing age in cats. Future researches using MRI scanners and a greater quantity of cats are needed in order to identify supplementary age-related changes.

Age-related hearing loss: Aquaporin 4 gene expression changes in the mouse cochlea and auditory midbrain

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Christensen, Nathan; D'Souza, Mary; Zhu, Xiaoxia; Frisina, Robert D.

2009-01-01

Presbycusis – age-related hearing loss, is the number one communication disorder, and one of the top three chronic medical conditions of our aged population. Aquaporins, particularly aquaporin 4 (Aqp4), are membrane proteins with important roles in water and ion flux across cell membranes, including cells of the inner ear and pathways of the brain used for hearing. To more fully understand the biological bases of presbycusis, 39 CBA mice, a well-studied animal model of presbycusis, underwent non-invasive hearing testing as a function of sound frequency (auditory brainstem response – ABR thresholds, and distortion-product otoacoustic emission – DPOAE magnitudes), and were clustered into four groups based on age and hearing ability. Aqp4 gene expression, as determined by genechip microarray analysis and quantitative real-time PCR, was compared to the young adult control group in the three older groups: middle aged with good hearing, old age with mild presbycusis, and old age with severe presbycusis. Linear regression and ANOVA showed statistically significant changes in Aqp4 gene expression and ABR and DPOAE hearing status in the cochlea and auditory midbrain – inferior colliculus. Down-regulation in the cochlea was seen, and an initial down-, then up-regulation was discovered for the inferior colliculus Aqp4 expression. It is theorized that these changes in Aqp4 gene expression represent an age-related disruption of ion flux in the fluids of the cochlea that are responsible for ionic gradients underlying sound transduction in cochlear hair cells necessary for hearing. In regard to central auditory processing at the level of the auditory midbrain, aquaporin gene expression changes may affect neurotransmitter cycling involving supporting cells, thus impairing complex sound neural processing with age. PMID:19070604

Overview of the age-related degradation of nuclear power plant structures

International Nuclear Information System (INIS)

Deng, Daniel

2004-01-01

License renewal of nuclear power plants is an issue of increasing interest to the U.S. nuclear industry and the U.S. NRC. This paper presents and evaluates the plausible age-related degradation mechanisms that may affect the concrete and steel containment structures and other Class I structures to continue to perform their safety functions. Preventive and/or mitigative options are outlined for managing degradation mechanisms that could significantly affect plant performance during the license renewal period. The provided technical information and the degradation management options may be used as references for comparison with plant specific conditions to ensure that age-related degradation is controlled during the license renewal term. Plausible degradation mechanisms described and analyzed as they may affect the concrete, reinforcing steel, containment steel shell, prestressed-tendon, steel liner and other structural components typically used in Class I structures. The significance of these age-related degradation mechanisms to the structural components are evaluated, giving consideration to the design basis and quality of construction; typical service conditions; operating and maintenance history; and current test, inspection and refurbishment practices for containment and Class I structures. Degradation mechanisms which cannot be generically dispositioned on the basis of the two-step approach: (1) they will not cause significant degradation, or (2) any potential degradation will be bounded by current test, inspection, analytical evaluation, and/or refurbishment programs are identified. Aging degradation management measures are recommended to address the remaining age-related degradation mechanisms. A three-phase approach for the management of the containment and Class I structures is introduced. Various techniques, testing tools and the acceptable criteria for each step of the evaluation of the structures status are provided. The preventive and mitigative

Age-related alteration in the composition of immunocompetent blood cells in atomic bomb survivors

International Nuclear Information System (INIS)

Kusunoki, Yoichiro; Akiyama, Mitoshi; Kyoizumi, Seishi; Bloom, E.T.; Makinodan, Takashi; California Univ., Los Angeles

1988-01-01

1328 survivors of Hiroshima were studied for alterations in the number of blood lymphocytes belonging to T-cell subpopulations, CD19 antigen-positive B cells and Leu 7 and CD16 antigen-positive lymphocytes. With increasing age, significant decreasing trends in the numbers of some lymphocytes in T-cell subpopulations and of B-cells were seen. The number of blood lymphocytes positive for CD5 antigen was significantly lower in those exposed to radiation (> 1Gy) in the older age group (more than 30 years at the time of bombing) and a similar tendency for decreases in the numbers of CD4, CD8, and CD19 antigen-positive cells was observed, but differences were not significant. The results suggest aging of the T-cell related immune system is accelerated in the irradiated people of advanced age, explained by the age-related decrease in thymic function in those subjects. The number of Leu 7 or CD19 antigen-positive cells was found to be increased significantly in the older age group compared to the younger, although there was little dose dependence. (U.K.)

Age-Related Change in Vestibular Ganglion Cell Populations in Individuals With Presbycusis and Normal Hearing.

Science.gov (United States)

Gluth, Michael B; Nelson, Erik G

2017-04-01

We sought to establish that the decline of vestibular ganglion cell counts uniquely correlates with spiral ganglion cell counts, cochlear hair cell counts, and hearing phenotype in individuals with presbycusis. The relationship between aging in the vestibular system and aging in the cochlea is a topic of ongoing investigation. Histopathologic age-related changes the vestibular system may mirror what is seen in the cochlea, but correlations with hearing phenotype and the impact of presbycusis are not well understood. Vestibular ganglion cells, spiral ganglion cells, and cochlear hair cells were counted in specimens from individuals with presbycusis and normal hearing. These were taken from within a large collection of processed human temporal bones. Correlations between histopathology and hearing phenotype were investigated. Vestibular ganglion cell counts were positively correlated with spiral ganglion cell counts and cochlear hair cell counts and were negatively correlated with hearing phenotype. There was no statistical evidence on linear regression to suggest that the relationship between age and cell populations differed significantly according to whether presbycusis was present or not. Superior vestibular ganglion cells were more negatively correlated with age than inferior ganglion cells. No difference in vestibular ganglion cells was noted based on sex. Vestibular ganglion cell counts progressively deteriorate with age, and this loss correlates closely with changes in the cochlea, as well as hearing phenotype. However, these correlations do not appear to be unique in individuals with presbycusis as compared with those with normal hearing.

Relative age and age sequence of fractions of soil organic matter

International Nuclear Information System (INIS)

Scharpenseel, H.W.

1975-01-01

Natural radiocarbon measurements on soil fractions provide information regarding the chances of separating the ''old biologically inert carbon'' out of samples of recent soil material. Beyond this, the relative fraction ages are scrutinized for the sequential order of the origin of the fractions within the biosynthetic reaction chain of soil humic matter. Among all fractions compared (classic humic matter fractionation by alkali and acid treatment; successive extraction with organic solvents of increasing polarity; separation according to particle size by Sephadex gel filtration; hydrolysis residue) the 6 n HCl hydrolysis residue shows the most consistent significant age increment. Repeated exhaustive hydrolysis treatment of the same sample material is still pending. All other fraction types indicate an age pattern under strong predetermination by method of origin, e.g., existence or lack of hydromorphy, without an evident enrichment of the ''old biologically inert carbon''. Among the organic extracts, no persistent age hierarchy is noticeable, whereas the classical fractions follow an age sequence mainly parallel to an increase of the molecular weight. Hymatomelanic acids appear rejuvenated by relics of recent carbon derived from the extractant ethanol. Grey humic acids are older than the brown humic acids, humines from fully terrestrial soil environment are older than humic acids, while in hydromorphic soils, cold alkali insoluble young C-compounds seem to be conserved which are liable to falsify rejuvenation of the humines

Clinical significance of AGE-RAGE axis in colorectal cancer: associations with glyoxalase-I, adiponectin receptor expression and prognosis

International Nuclear Information System (INIS)

Sakellariou, Stratigoula; Fragkou, Paraskevi; Levidou, Georgia; Gargalionis, Antonios N.; Piperi, Christina; Dalagiorgou, Georgia; Adamopoulos, Christos; Saetta, Angelica; Agrogiannis, George; Theohari, Irini; Sougioultzis, Stavros; Tsioli, Panagiota; Karavokyros, Ioannis; Tsavaris, Nikolaos; Kostakis, Ioannis D.; Zizi-Serbetzoglou, Adamantia; Vandoros, Gerasimos P.; Patsouris, Efstratios; Korkolopoulou, Penelope

2016-01-01

Advanced glycation end products (AGEs) and their receptor RAGE emerge as important pathogenic contributors in colorectal carcinogenesis. However, their relationship to the detoxification enzyme Glyoxalase (GLO)-I and Adiponectin receptors (AdipoR1, AdipoR2) in colorectal carcinoma (CRC) is currently understudied. In the present study, we investigated the expression levels of the above molecules in CRC compared to adjacent non-tumoral tissue and their potential correlation with clinicopathological characteristics and patients’ survival. We analyzed the immunohistochemical expression of AGE, RAGE, GLO-1, AdipoR1 and AdipoR2 in 133 primary CRC cases, focusing on GLO-I. The tumour MSI status was further assessed in mucinous carcinomas. Western immunoblotting was employed for validation of immunohistochemical data in normal and tumoral tissues as well in three CRC cell lines. An independent set of 55 patients was also used to validate the results of univariate survival analysis regarding GLO-I. CRC tissue showed higher intensity of both AGE and RAGE expression compared with normal colonic mucosa which was negative for GLO-I in most cases (78 %). Western immunoblotting confirmed AGE, RAGE and GLO-I overexpression in tumoral tissue. GLO-I expression was directly related to RAGE and inversely related to AGE immunolabeling. There was a trend towards higher expression of all markers (except for RAGE) in the subgroup of mucinous carcinomas which, although of borderline significance, seemed to be more prominent for AdipoR1 and AGE. Additionally, AGE, AdipoR1 and Adipo R2 expression was related to tumor grade, whereas GLO-1 and AdipoR1 to T-category. In survival analysis, AdipoR2 and GLO-I overexpression predicted shortened survival in the entire cohort and in early stage cases, an effect which for GLO-I was reproduced in the validation cohort. Moreover, GLO-I emerged as an independent prognosticator of adverse significance in the patients’ cohort. We herein provide novel

Age-related changes in the retinal pigment epithelium (RPE.

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Xiaorong Gu

Full Text Available Age-related changes in the retina are often accompanied by visual impairment but their mechanistic details remain poorly understood.Proteomic studies were pursued toward a better molecular understanding of retinal pigment epithelium (RPE aging mechanisms. RPE cells were isolated from young adults (3-4 month-old and old (24-25 month-old F344BN rats, and separated into subcellular fractions containing apical microvilli (MV and RPE cell bodies (CB lacking their apical microvilli. Proteins were extracted in detergent, separated by SDS-PAGE, digested in situ with trypsin and analyzed by LC MS/MS. Select proteins detected in young and old rat RPE were further studied using immunofluorescence and Western blot analysis.A total of 356 proteins were identified in RPE MV from young and 378 in RPE MV from old rats, 48% of which were common to each age group. A total of 897 proteins were identified in RPE CB from young rats and 675 in old CB, 56% of which were common to each age group. Several of the identified proteins, including proteins involved in response to oxidative stress, displayed both quantitative and qualitative changes in overall abundance during RPE aging. Numerous proteins were identified for the first time in the RPE. One such protein, collectrin, was localized to the apical membrane of apical brush border of proximal tubules where it likely regulates several amino acid transporters. Elsewhere, collectrin is involved in pancreatic β cell proliferation and insulin secretion. In the RPE, collectrin expression was significantly modulated during RPE aging. Another age-regulated, newly described protein was DJ-1, a protein extensively studied in brain where oxidative stress-related functions have been described.The data presented here reveals specific changes in the RPE during aging, providing the first protein database of RPE aging, which will facilitate future studies of age-related retinal diseases.

Cognitive and neuropsychological underpinnings of relational and conjunctive working memory binding across age.

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van Geldorp, Bonnie; Parra, Mario A; Kessels, Roy P C

2015-01-01

The ability to form associations (i.e., binding) is critical for memory formation. Recent studies suggest that aging specifically affects relational binding (associating separate features) but not conjunctive binding (integrating features within an object). Possibly, this dissociation may be driven by the spatial nature of the studies so far. Alternatively, relational binding may simply require more attentional resources. We assessed relational and conjunctive binding in three age groups and we included an interfering task (i.e., an articulatory suppression task). Binding was examined in a working memory (WM) task using non-spatial features: shape and colour. Thirty-one young adults (mean age = 22.35), 30 middle-aged adults (mean age = 54.80) and 30 older adults (mean age = 70.27) performed the task. Results show an effect of type of binding and an effect of age but no interaction between type of binding and age. The interaction between type of binding and interference was significant. These results indicate that aging affects relational binding and conjunctive binding similarly. However, relational binding is more susceptible to interference than conjunctive binding, which suggests that relational binding may require more attentional resources. We suggest that a general decline in WM resources associated with frontal dysfunction underlies age-related deficits in WM binding.

The effect of normal aging and age-related macular degeneration on perceptual learning.

Science.gov (United States)

Astle, Andrew T; Blighe, Alan J; Webb, Ben S; McGraw, Paul V

2015-01-01

We investigated whether perceptual learning could be used to improve peripheral word identification speed. The relationship between the magnitude of learning and age was established in normal participants to determine whether perceptual learning effects are age invariant. We then investigated whether training could lead to improvements in patients with age-related macular degeneration (AMD). Twenty-eight participants with normal vision and five participants with AMD trained on a word identification task. They were required to identify three-letter words, presented 10° from fixation. To standardize crowding across each of the letters that made up the word, words were flanked laterally by randomly chosen letters. Word identification performance was measured psychophysically using a staircase procedure. Significant improvements in peripheral word identification speed were demonstrated following training (71% ± 18%). Initial task performance was correlated with age, with older participants having poorer performance. However, older adults learned more rapidly such that, following training, they reached the same level of performance as their younger counterparts. As a function of number of trials completed, patients with AMD learned at an equivalent rate as age-matched participants with normal vision. Improvements in word identification speed were maintained at least 6 months after training. We have demonstrated that temporal aspects of word recognition can be improved in peripheral vision with training across a range of ages and these learned improvements are relatively enduring. However, training targeted at other bottlenecks to peripheral reading ability, such as visual crowding, may need to be incorporated to optimize this approach.

Relative Age in School and Suicide among Young Individuals in Japan: A Regression Discontinuity Approach.

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Tetsuya Matsubayashi

Full Text Available Evidence collected in many parts of the world suggests that, compared to older students, students who are relatively younger at school entry tend to have worse academic performance and lower levels of income. This study examined how relative age in a grade affects suicide rates of adolescents and young adults between 15 and 25 years of age using data from Japan.We examined individual death records in the Vital Statistics of Japan from 1989 to 2010. In contrast to other countries, late entry to primary school is not allowed in Japan. We took advantage of the school entry cutoff date to implement a regression discontinuity (RD design, assuming that the timing of births around the school entry cutoff date was randomly determined and therefore that individuals who were born just before and after the cutoff date have similar baseline characteristics.We found that those who were born right before the school cutoff day and thus youngest in their cohort have higher mortality rates by suicide, compared to their peers who were born right after the cutoff date and thus older. We also found that those with relative age disadvantage tend to follow a different career path than those with relative age advantage, which may explain their higher suicide mortality rates.Relative age effects have broader consequences than was previously supposed. This study suggests that policy intervention that alleviates the relative age effect can be important.

Assessing Age-Related Etiologic Heterogeneity in the Onset of Islet Autoimmunity

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Brittni N. Frederiksen

2015-01-01

Full Text Available Type 1 diabetes (T1D, a chronic autoimmune disease, is often preceded by a preclinical phase of islet autoimmunity (IA where the insulin-producing beta cells of the pancreas are destroyed and circulating autoantibodies can be detected. The goal of this study was to demonstrate methods for identifying exposures that differentially influence the disease process at certain ages by assessing age-related heterogeneity. The Diabetes Autoimmunity Study in the Young (DAISY has followed 2,547 children at increased genetic risk for T1D from birth since 1993 in Denver, Colorado, 188 of whom developed IA. Using the DAISY population, we evaluated putative determinants of IA, including non-Hispanic white (NHW ethnicity, maternal age at birth, and erythrocyte membrane n-3 fatty acid (FA levels, for age-related heterogeneity. A supremum test, weighted Schoenfeld residuals, and restricted cubic splines were used to assess nonproportional hazards, that is, an age-related association of the exposure with IA risk. NHW ethnicity, maternal age, and erythrocyte membrane n-3 FA levels demonstrated a significant age-related association with IA risk. Assessing heterogeneity in disease etiology enables researchers to identify associations that may lead to better understanding of complex chronic diseases.

Men and mice: Relating their ages.

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Dutta, Sulagna; Sengupta, Pallav

2016-05-01

Since the late 18th century, the murine model has been widely used in biomedical research (about 59% of total animals used) as it is compact, cost-effective, and easily available, conserving almost 99% of human genes and physiologically resembling humans. Despite the similarities, mice have a diminutive lifespan compared to humans. In this study, we found that one human year is equivalent to nine mice days, although this is not the case when comparing the lifespan of mice versus humans taking the entire life at the same time without considering each phase separately. Therefore, the precise correlation of age at every point in their lifespan must be determined. Determining the age relation between mice and humans is necessary for setting up experimental murine models more analogous in age to humans. Thus, more accuracy can be obtained in the research outcome for humans of a specific age group, although current outcomes are based on mice of an approximate age. To fill this gap between approximation and accuracy, this review article is the first to establish a precise relation between mice age and human age, following our previous article, which explained the relation in ages of laboratory rats with humans in detail. Copyright © 2015 Elsevier Inc. All rights reserved.

Age-related changes in hand dominance and functional asymmetry in older adults.

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Anna Sebastjan

Full Text Available The aim of the study was to investigate fine motor performance and ascertain age-related changes in laterality between the dominant and non-dominant hand. A representative sample of 635 adults (144 males and 491 females aged 50 years and over completed a test battery MLS (Motor Performance Series to assess a broad range of hand functions. Functional asymmetry was observed in all four motor tests (postural tremor, aiming, tapping, and inserting long pins. Significant differences between the dominant and non-dominant hand were obtained in both sexes across all age groups, except in the oldest female group (age >70 for the aiming (number of hits and errors and postural tremor (number of errors tasks. These differences in age-related changes may be attributed to hemispheric asymmetry, environmental factors, or use-dependent plasticity. Conflicting evidence in the literature warrants additional research to better explain age-related alterations of hand dominance and manual performance in old age.

Bodacious Berry, Potency Wood and the Aging Monster: Gender and Age Relations in Anti-Aging Ads

Science.gov (United States)

Calasanti, Toni

2007-01-01

This paper situates age discrimination within a broader system of age relations that intersects with other inequalities, and then uses that framework to analyze internet advertisements for the anti-aging industry. Such ads reinforce age and gender relations by positing old people as worthwhile only to the extent that they look and act like those…

Maturity Status Strongly Influences the Relative Age Effect in International Elite Under-9 Soccer

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Lisa Müller, Josef Gehmaier, Christoph Gonaus, Christian Raschner, Erich Müller

2018-06-01

Full Text Available The aim of the study was to assess the role of the relative age effect (RAE and to investigate the influence of the biological maturity status on the RAE in international under-9 soccer. The birth dates of 222 male participants of the U9 Eurochampionship Soccer Tournament in Vienna in 2016 were analyzed and divided into four relative age quarters (Q1-Q4 and the biological maturity status was assessed with the age at peak height velocity (APHV method. Based on the mean±standard deviation of the APHV, the athletes were divided into three groups of maturity: early, normal and late maturing. Chi-Square-tests were used to assess the difference between the observed and the expected even relative age quarter distribution and to evaluate the difference between the observed distribution of early, normal and late maturing athletes and the expected normal distribution. A univariate analysis of variance was performed to assess differences in the APHV between the relative age quarters. A RAE was present (χ2 = 23.87; p < 0.001; ω = 0.33. A significant difference was found in APHV between the four relative age quarters (F = 9.906; p < 0.001; relatively older athletes were significantly less mature. A significant difference was found between the distribution of early, normal and late maturing athletes and the expected normal distribution for athletes of Q1 (high percentage of late maturing athletes: 27%; χ2 = 17.69; p < 0.001; ω = 0.46 and of Q4 (high percentage of early maturing soccer players: 31%; χ2 = 12.08; p = 0.002; ω = 0.58. These findings demonstrated that the selection process in international soccer, with athletes younger than 9 years, seems to be associated with the biological maturity status and the relative age. Relatively younger soccer players seem to have a better chance for selection for international tournaments, if they enter puberty at an earlier age, whereas relatively older athletes seem to have an increased likelihood for

Age-Related Decline in Controlled Retrieval: The Role of the PFC and Sleep

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Kristine A. Wilckens

2012-01-01

Full Text Available Age-related cognitive impairments often include difficulty retrieving memories, particularly those that rely on executive control. In this paper we discuss the influence of the prefrontal cortex on memory retrieval, and the specific memory processes associated with the prefrontal cortex that decline in late adulthood. We conclude that preretrieval processes associated with preparation to make a memory judgment are impaired, leading to greater reliance on postretrieval processes. This is consistent with the view that impairments in executive control significantly contribute to deficits in controlled retrieval. Finally, we discuss age-related changes in sleep as a potential mechanism that contributes to deficiencies in executive control that are important for efficient retrieval. The sleep literature points to the importance of slow-wave sleep in restoration of prefrontal cortex function. Given that slow-wave sleep significantly declines with age, we hypothesize that age-related changes in slow-wave sleep could mediate age-related decline in executive control, manifesting a robust deficit in controlled memory retrieval processes. Interventions, like physical activity, that improve sleep could be effective methods to enhance controlled memory processes in late life.

The Age-Related Changes in Cartilage and Osteoarthritis

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YongPing Li

2013-01-01

Full Text Available Osteoarthritis (OA is closely associated with aging, but its underlying mechanism is unclear. Recent publications were reviewed to elucidate the connection between aging and OA. With increasing OA incidence, more senior people are facing heavy financial and social burdens. Age-related OA pathogenesis is not well understood. Recently, it has been realized that age-related changes in other tissues besides articular cartilage may also contribute to OA development. Many factors including senescence-related secretory phenotypes, chondrocytes’ low reactivity to growth factors, mitochondrial dysfunction and oxidative stress, and abnormal accumulation of advanced glycation end products (AGEs may all play key roles in the pathogenesis of age-related OA. Lately, epigenetic regulation of gene expression was recognized for its impact on age-related OA pathogenesis. Up to now, few studies have been reported about the role of miRNA and long-noncoding RNA (lncRNA in age-related OA. Research focusing on this area may provide valuable insights into OA pathogenesis. OA-induced financial and social burdens have become an increasingly severe threat to older population. Age-related changes in noncartilage tissue should be incorporated in the understanding of OA development. Growing attention on oxidative stress and epigenetics will provide more important clues for the better understanding of the age-related OA.

Age-related differences in working hours among male and female GPs: an SMS-based time use study.

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van Hassel, Daniël; van der Velden, Lud; de Bakker, Dinny; Batenburg, Ronald

2017-12-19

In several countries, the number of hours worked by general practitioners (GPs) has decreased, raising concern about current and impending workforce shortages. This shorter working week has been ascribed both to the feminisation of the workforce and to a younger generation of GPs who prefer more flexible working arrangements. There is, however, limited insight into how the impact of these determinants interact. We investigated the relative importance of differences in GPs' working hours in relation to gender, age, and employment position. An analysis was performed on real-time monitoring data collected by sending SMS text messages to 1051 Dutch GPs, who participated during a 1-week time use study. We used descriptive statistics, independent sample t-tests, and one-way ANOVA analysis to compare the working time of different GP groups. A path analysis was conducted to examine the difference in working time by gender, age, employment position, and their combinations. Female GPs worked significantly fewer hours than their male peers. GPs in their 50s worked the highest number of hours, followed by GPs age 60 and older. GPs younger than 40 worked the lowest number of hours. This relationship between working hours and age was not significantly different for women and men. As shown by path analysis, female GPs consistently worked fewer hours than their male counterparts, regardless of their age and employment position. The relationship between age and working hours was largely influenced by gender and employment position. The variation in working hours among GPs can be explained by the combination of gender, age, and employment position. Gender appears to be the most important predictor as the largest part of the variation in working hours is explained by a direct effect of this variable. It has previously been reported that the difference in working hours between male and female GPs had decreased over time. However, our findings suggest that gender remains a critical

Incentive relativity in middle aged rats.

Science.gov (United States)

Justel, N; Mustaca, A; Boccia, M; Ruetti, E

2014-01-24

Response to a reinforcer is affected by prior experience with different reward values of that reward, a phenomenon known as incentive relativity. Two different procedures to study this phenomenon are the incentive downshift (ID) and the consummatory anticipatory negative contrast (cANC), the former is an emotional-cognitive protocol and the latter cognitive one. Aged rodents, as also well described in aged humans, exhibit alterations in cognitive functions. The main goal of this work was to evaluate the effect of age in the incentive' assessment using these two procedures. The results indicated that aged rats had an adequate assessment of the rewards but their performance is not completely comparable to that of young subjects. They recover faster from the ID and they had a cognitive impairment in the cANC. The results are discussed in relation to age-related changes in memory and emotion. Copyright © 2013 Elsevier Ireland Ltd. All rights reserved.

Towards an explanation of age-related difficulties in crossing a two-way street

OpenAIRE

Dommes , Aurélie; LE LAY , Tristan; Vienne , Fabrice; DANG , Nguyen-Thong; PERROT BEAUDOIN , Alexandra; Do , Manh Cuong

2015-01-01

Crossing a two-way street is a complex task that involves visual, cognitive and motor abilities, all of which are known to decline with ageing. In particular, older pedestrians may experience difficulties when crossing two-way streets because of incorrect gap acceptance choices and impossible or unperceived evasive actions. To understand the overrepresentation of older pedestrians in crash statistics, several experimental studies have sought to identify traffic-related factors as well as thos...

Comprehensive identification of age-related lipidome changes in rat amygdala during normal aging.

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Roman Šmidák

Full Text Available Brain lipids are integral components of brain structure and function. However, only recent advancements of chromatographic techniques together with mass spectrometry allow comprehensive identification of lipid species in complex brain tissue. Lipid composition varies between the individual areas and the majority of previous reports was focusing on individual lipids rather than a lipidome. Herein, a mass spectrometry-based approach was used to evaluate age-related changes in the lipidome of the rat amygdala obtained from young (3 months and old (20 months males of the Sprague-Dawley rat strain. A total number of 70 lipid species with significantly changed levels between the two animal groups were identified spanning four main lipid classes, i.e. glycerolipids, glycerophospholipids, sphingolipids and sterol lipids. These included phospholipids with pleiotropic brain function, such as derivatives of phosphatidylcholine, phosphatidylserine, and phosphatidylethanolamine. The analysis also revealed significant level changes of phosphatidic acid, diacylglycerol, sphingomyelin and ceramide that directly represent lipid signaling and affect amygdala neuronal activity. The amygdala is a crucial brain region for cognitive functions and former studies on rats and humans showed that this region changes its activity during normal aging. As the information on amygdala lipidome is very limited the results obtained in the present study represent a significant novelty and may contribute to further studies on the role of lipid molecules in age-associated changes of amygdala function.

Gene expression changes for antioxidants pathways in the mouse cochlea: relations to age-related hearing deficits.

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Sherif F Tadros

Full Text Available Age-related hearing loss - presbycusis - is the number one neurodegenerative disorder and top communication deficit of our aged population. Like many aging disorders of the nervous system, damage from free radicals linked to production of reactive oxygen and/or nitrogen species (ROS and RNS, respectively may play key roles in disease progression. The efficacy of the antioxidant systems, e.g., glutathione and thioredoxin, is an important factor in pathophysiology of the aging nervous system. In this investigation, relations between the expression of antioxidant-related genes in the auditory portion of the inner ear - cochlea, and age-related hearing loss was explored for CBA/CaJ mice. Forty mice were classified into four groups according to age and degree of hearing loss. Cochlear mRNA samples were collected and cDNA generated. Using Affymetrix® GeneChip, the expressions of 56 antioxidant-related gene probes were analyzed to estimate the differences in gene expression between the four subject groups. The expression of Glutathione peroxidase 6, Gpx6; Thioredoxin reductase 1, Txnrd1; Isocitrate dehydrogenase 1, Idh1; and Heat shock protein 1, Hspb1; were significantly different, or showed large fold-change differences between subject groups. The Gpx6, Txnrd1 and Hspb1 gene expression changes were validated using qPCR. The Gpx6 gene was upregulated while the Txnrd1 gene was downregulated with age/hearing loss. The Hspb1 gene was found to be downregulated in middle-aged animals as well as those with mild presbycusis, whereas it was upregulated in those with severe presbycusis. These results facilitate development of future interventions to predict, prevent or slow down the progression of presbycusis.

Epigenetic age analysis of children who seem to evade aging.

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Walker, Richard F; Liu, Jia Sophie; Peters, Brock A; Ritz, Beate R; Wu, Timothy; Ophoff, Roel A; Horvath, Steve

2015-05-01

We previously reported the unusual case of a teenage girl stricken with multifocal developmental dysfunctions whose physical development was dramatically delayed resulting in her appearing to be a toddler or at best a preschooler, even unto the occasion of her death at the age of 20 years. Her life-long physician felt that the disorder was unique in the world and that future treatments for age-related diseases might emerge from its study. The objectives of our research were to determine if other such cases exist, and if so, whether aging is actually slowed. Of seven children characterized by dramatically slow developmental rates, five also had associated disorders displayed by the first case. All of the identified subjects were female. To objectively measure the age of blood tissue from these subjects, we used a highly accurate biomarker of aging known as "epigenetic clock" based on DNA methylation levels. No statistically significant differences in chronological and epigenetic ages were detected in any of the newly discovered cases.

Statistics and Corporate Environmental Management: Relations and Problems

DEFF Research Database (Denmark)

Madsen, Henning; Ulhøi, John Parm

1997-01-01

Statistical methods have long been used to analyse the macroeconomic consequences of environmentally damaging activities, political actions to control, prevent, or reduce these damages, and environmental problems in the natural environment. Up to now, however, they have had a limited and not very...... in the external environment. The nature and extent of the practical use of quantitative techniques in corporate environmental management systems is discussed on the basis of a number of company surveys in four European countries.......Statistical methods have long been used to analyse the macroeconomic consequences of environmentally damaging activities, political actions to control, prevent, or reduce these damages, and environmental problems in the natural environment. Up to now, however, they have had a limited and not very...... specific use in corporate environmental management systems. This paper will address some of the special problems related to the use of statistical techniques in corporate environmental management systems. One important aspect of this is the interaction of internal decisions and activities with conditions...

Quantitative analysis of cone photoreceptor distribution and its relationship with axial length, age, and early age-related macular degeneration.

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Ryo Obata

Full Text Available PURPOSE: It has not been clarified whether early age-related macular degeneration (AMD is associated with cone photoreceptor distribution. We used adaptive optics fundus camera to examine cone photoreceptors in the macular area of aged patients and quantitatively analyzed its relationship between the presence of early AMD and cone distribution. METHODS: Sixty cases aged 50 or older were studied. The eyes were examined with funduscopy and spectral-domain optical coherence tomography to exclude the eyes with any abnormalities at two sites of measurement, 2° superior and 5° temporal to the fovea. High-resolution retinal images with cone photoreceptor mosaic were obtained with adaptive optics fundus camera (rtx1, Imagine Eyes, France. After adjusting for axial length, cone packing density was calculated and the relationship with age, axial length, or severity of early AMD based on the age-related eye disease study (AREDS classification was analyzed. RESULTS: Patient's age ranged from 50 to 77, and axial length from 21.7 to 27.5 mm. Mean density in metric units and that in angular units were 24,900 cells/mm2, 2,170 cells/deg2 at 2° superior, and 18,500 cells/mm2, 1,570 cels/deg2 at 5° temporal, respectively. Axial length was significantly correlated with the density calculated in metric units, but not with that in angular units. Age was significantly correlated with the density both in metric and angular units at 2° superior. There was no significant difference in the density in metric and angular units between the eyes with AREDS category one and those with categories two or three. CONCLUSION: Axial length and age were significantly correlated with parafoveal cone photoreceptor distribution. The results do not support that early AMD might influence cone photoreceptor density in the area without drusen or pigment abnormalities.

Absence of age-related prefrontal NAA change in adults with autism spectrum disorders.

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